In November 1917, upon the disintegration of the Russian Empire, a diet of the Autonomous Governorate of Estonia, the Estonian Provincial Assembly, which had been elected in the spring of that year, proclaimed itself the highest authority in Estonia. Soon thereafter, the Bolsheviks dissolved the Estonian Provincial Assembly and temporarily forced the pro-independence Estonians underground in the capital Tallinn. A few months later, using the interval between the Red Army's retreat and the arrival of the Imperial German Army, the Salvation Committee of the Estonian National Council Maapäev issued the Estonian Declaration of Independence in Tallinn on 24 February 1918 and formed the Estonian Provisional Government. This first period of independence was extremely short-lived, as the German troops entered Tallinn on the following day. The German authorities recognized neither the provisional government, nor its claim for Estonia's independence, counting them as a self-styled group usurping sovereign rights of the Baltic nobility.
After the German Revolution with the capitulation of Imperial Germany, between the 11 and 14 November 1918, the representatives of Germany formally handed over political power to the Estonian Provisional Government. On 16 November the provisional government called for voluntary mobilization and began to organize the Estonian Army, with Konstantin Päts as Minister of War, Major General Andres Larka as the chief of staff, and Major General Aleksander Tõnisson as commander of the Estonian Army, initially consisting of one division.
In late November 1918, Soviet forces moved against Estonia. On 28 November 1918, the 6th Red Rifle Division struck the border town of Narva, which marked the beginning of the Estonian War of Independence.
The 6th Red Rifle Division attacked with 7,000 infantry, 22 field guns, 111 machine guns, an armored train, two armored vehicles, two airplanes, and the Bogatyr class cruiser Oleg supported by two destroyers. The town was defended by men of the Estonian Defence League (Home Guard) (consisting partly of secondary school students) and Infanterie-Regiment Nr. 405 of the German Army. The Reds captured Narva on 29 November, and the Infanterie-Regiment Nr. 405 withdrew westwards.
The Soviet 2nd Novgorod Division opened a second front south of Lake Peipus, with 7,000 infantry, 12 field guns, 50 machine guns, two armored trains, and three armored vehicles.
Estonian military forces at the time consisted of 2,000 men with light weapons and about 14,500 poorly armed men in the Estonian Defence League. The end of November 1918 saw the formation of the Baltic Battalion, primarily a mounted machine-gun company plus infantry. Estonia's Baltic German minority provided a sizable troop of volunteer militia for the Battalion, which was one of the first fighting units of the Estonian Army, and maintained staunch loyalty to the authority of in the Republic. This contrasts with the Baltische Landeswehr in Latvia.
The 49th Red Latvian Rifle Regiment took the Valga railway junction on 18 December and the city of Tartu on Christmas Eve. Also on Christmas Eve, the 6th Red Rifle Division captured the Tapa railway junction, advancing to within 34 kilometers of the nation's capital Tallinn. Estonian Bolsheviks declared the Estonian Workers' Commune in Narva.
By the end of the year, the 7th Red Army controlled Estonia along the front line 34 kilometers east of Tallinn, west from Tartu and south of Ainaži.
Colonel Johan Laidoner was appointed Commander in chief of the Estonian armed forces. He recruited 600 officers and 11,000 volunteers by 23 December 1918.
He reorganized the forces by setting up the 2nd Division in Southern Estonia under the command of Colonel Viktor Puskar, along with commando type units, such as the Tartumaa Partisan Battalion and the Kalevi Malev Battalion.
The national government obtained foreign assistance. On 5 December, Finland delivered 5,000 rifles and 20 field guns along with ammunition.
A British Royal Navy squadron commanded by Rear Admiral Sir Edwyn Alexander-Sinclair arrived at Tallinn on 31 December, and delivered 6,500 rifles, 200 machine guns, and two field guns. The squadron captured two Russian destroyers, Spartak and Avtroil, and turned them over to Estonia, which renamed them Vambola and Lennuk.
On 2 January, Finnish volunteer units with 2,000 men arrived in Estonia. Three armored trains were built in Tallinn under the command of Captain Anton Irv.
By the beginning of 1919, the Estonian Army had increased its ranks to a total of 13,000 men, with 5,700 on the front facing 8,000 Soviets. The strengthened Estonian Army stopped the 7th Red Army's advance in its tracks between 2 and 5 January 1919 and went on the counter-offensive on 7 January.
Tapa was liberated two days later in a campaign highlighted by the implementation of the highly successful "soomusrongid" (armoured trains). This turn of events was swiftly followed by the liberaton of the sizable town of Rakvere on 12 January.
In liberating Narva, a 1,000-strong Finnish-Estonian force landed at Utria to the rear of the Soviet 6th Rifle Division on 17 January. In so doing, retreat eastward for the Soviet forces was precluded. The following day Narva was liberated.
Consequent to this the northeastern front stabilized along the Narva river. Within 11 days, the 1st Division had advanced 200 km.
In the southern sphere-of-conflict Tartu was liberated through the rapid deployment of armored trains and the Tartumaa Partisan Battalion. The 2nd Division continued to advance southwards facing increasing Soviet resistance. In the Battle of Paju, the Tartumaa Partisan Battalion and the Finnish volunteers drove the Latvian Riflemen out of Valga on 31 January.
The 7th Red Army was routed outside the boundaries of contemporary Estonia (at that time) and the battle-front continued outwards into the ancient, historical Estonian settlement area. The second half of February saw the Estonian southward advance capture Salacgrīva and Alūksne. This advance was soon stopped by a Soviet buildup ostensibly for a new expansionist offensive into Estonia. On the first Independence Day of 24 February 1919, the pro-independence Estonian forces on the front consisted of 19,000 men, 70 field guns, and 230 machine guns. Estonia had become the first country to repel the Soviet westward offensive.
In the second half of February, the red armies started the new Soviet offensive to capture Estonia. To this end the Soviets established what was referred to as the new 'Estonian' Red Army. This sizable force consisted upwards of 80,000 conscripts.
In positions along the Narva River the Estonian 1st Division and their allied White Russian Northern Corps repelled the 7th Red Army's attacks. The red army heavily bombarded Narva, leaving about 2,000 people homeless yet ultimately failed to capture the city. The majority of Soviet forces were concentrated at and along the southern front. The so-called 'Estonian' Red Army captured Alūksne, Setomaa, Vastseliina, and Räpina parishes by 15 March.
Having received reinforcements, the Estonian 2nd Division counterattacked and regained Petseri by 29 March. Subsequently, the 'Estonian' Red Army was pushed behind the Optjok River.
On 27 March, the Estonian 3rd Division was deployed along the western flank of the southern front under the command of Major-General Ernst Põdder. At Võru, the situation became critical on 22 April when the Red Army approached to within 1.5 km of the town. Heavy fighting continued at the southeastern front up to the first half of May.
On 25 April, the Latvian Riflemen captured Rūjiena, but were soon pushed back by the 3rd Division to Salacgrīva-Seda-Gauja line.
On 5–7 April 1919 the Estonian Constituent Assembly was elected. The elections were won by the Left and Centre parties. The 120 members of the Constituent Assembly met at the opening session on 23 April, and elected Social Democrat August Rei as chairman. The provisional government retired, and a new government headed by Otto Strandman was formed. On 4 June the assembly adopted a temporary Constitution of Estonia. On 10 October the Land Reform Act was passed, which confiscated and redistributed the large Baltic German estates that covered more than half of the territory of Estonia.
Estonia actively helped to organize White Russian, Latvian and Ingrian forces on the territory of the Republic. The White Russian Northern Corps had been organizing in Estonia since December 1918. On 18 February, an agreement was signed between Estonia and Latvia, which allowed formation of Latvian forces under Estonian command, but using them only on the southern front. The North Latvian Brigade under the command of Jorģis Zemitāns was formed from the citizens of Latvia who had fled to Estonia. In March 1919, an agreement was signed with the Ingrian National People’s Committee for the formation of an Ingrian battalion. By May 1919, there were 6,000 Russians, 4,000 Latvians and 700 Ingrians in their respective national units.
Although the Estonian Army had attained control over its country, its opposite red armies were still active. The Estonian High Command decided to push their defense lines across the border into Russia in support of the White Russian Northern Corps. On 13 May, the Northern Corps went on the offensive at Narva, catching the Soviets by surprise and destroying their 6th Division. The offensive was supported along the Gulf of Finland's coast by the British and Estonian navy and marines. With the front approaching, the garrison of the Krasnaya Gorka fort mutinied. But the 7th Red Army received reinforcements and counterattacked, pushing the White Russians back, until the front was stabilised with the support from the Estonian 1st Division on the Luga and Saba rivers.
The offensive of the Estonian Petseri Battle Group began on 24 May. On the same day 1st Estonian Communist Regiment of 600 troops together with Leonhard Ritt, commander of the Estonian 1st Rifle Division switched sides. Offensive destroyed the Estonian Red Army, captured Pskov on 25 May and cleared the territory between Estonia and the Velikaya River of Soviet forces. A few days later White Russian forces arrived in Pskov, but as they were unable to defend the town on their own, some Estonian forces remained in Pskov, while the rest were pulled back to the state border. The Northern Corps mobilised members of the local population in the Pskov region. On 19 June 1919, the Estonian Commander-in-Chief General Johan Laidoner rescinded his command over the White Russians, and they were renamed the Northwestern Army. Shortly afterwards, General Nikolai N. Yudenich took command of the troops.
Simultaneously with the Pskov offensive Estonian 2nd and 3rd divisions also started southward offensive into Northern-Latvia. By end of May they had captured Alūksne and Valmiera. Due simultaneous German-Latvian offensive in Western-Latvia situation was becoming very difficult for the Soviets. On 31 May Estonian cavalry regiment led by Gustav Jonson reached Gulbene capturing large amount of rolling stock, including 2 armoured trains. Rapid offensive of 2nd Division, spearheaded by its cavalry regiment, continued and on 6 June it crossed Daugava river and captured Jēkabpils. But 3rd Division could not support advance of 2nd division anymore as it was now facing a new enemy: the Baltische Landeswehr.
The war against the Baltische Landeswehr broke out on the southern front in Latvia on 5 June 1919. The Latvian democrats led by Kārlis Ulmanis had declared independence like in Estonia, but were soon pushed back to Liepāja by Soviet forces, where the German VI Reserve Corps finally stopped their advance. This German force, led by general Rüdiger von der Goltz, consisted of the Baltische Landeswehr formed from Baltic Germans, the Guards Reserve Division of former Imperial German Army soldiers who had stayed in Latvia, and the Freikorps Iron Division of volunteers motivated by prospects of acquiring properties in the Baltics. This was possible because the terms of their armistice with the Western Allies obliged the Germans to maintain their armies in the East to counter the Bolshevist threat. The VI Reserve Corps also included the 1st Independent Latvian Battalion led by Oskars Kalpaks, which consisted of ethnic Latvians loyal to the Provisional Government of Latvia.
The Germans disrupted the organization of Latvian national forces, and on 16 April 1919 the Provisional Government was toppled and replaced with the pro-German puppet Provisional Government of Latvia led by Andrievs Niedra. Ulmanis took refuge aboard the steamship "Saratow" under Entente protection. The VI Reserve Corps pushed the Soviets back, capturing Riga on 23 May, continued to advance northwards, and demanded that the Estonian Army ended its occupation of parts of northern Latvia. The real intent of the VI Reserve Corps was to annex Estonia into a German-dominated puppet state.
On 3 June, Estonian General Laidoner issued an ultimatum demanding that German forces must pull back southwards, leaving the broad gauge railway between Ieriķi and Gulbene under Estonian control. When Estonian armoured trains moved out on 5 June to check compliance with this demand, the Baltische Landeswehr attacked them, unsuccessfully. The following day, the Baltische Landeswehr captured Cēsis. On 8 June, an Estonian counterattack was repelled. First clashes demonstrated that the VI Reserve Corps was stronger and better equipped than the Soviets. On 10 June, with Entente mediation, a ceasefire was made. Despite the Entente demand for the German force to pull behind the line demanded by the Estonians, von der Goltz refused and demanded Estonian withdrawal from Latvia, threatening to continue fighting. On 19 June, fighting resumed with an assault of the Iron Division on positions of the Estonian 3rd Division near Limbaži and Straupe, starting the Battle of Cēsis. At that time, the 3rd Estonian Division, including the 2nd Latvian Cēsis regiment under Colonel Krišjānis Berķis, had 5990 infantry and 125 cavalry. Intensive German attacks on Estonian positions continued up to 22 June, without achieving a breakthrough. On 23 June, the Estonian 3rd Division counterattacked, recapturing Cēsis. The anniversary of the Battle of Cēsis (Võnnu lahing in Estonian) is celebrated in Estonia as the Victory Day.
The Estonian 3rd Division continued their advance towards Riga. On 3 July, when the Estonian forces were at the outskirts of Riga, a ceasefire was made on the demand of the Entente and the Ulmanis government was restored in Riga. The German forces were ordered to leave Latvia, the Baltische Landeswehr was put under the command of the Latvian Provisional Government and sent to fight against the Red Army. However, to circumvent Entente's orders, the troops of the disbanded VI Reserve Corps, instead of leaving, were incorporated into the West Russian Volunteer Army, officially hired by the German puppet Government of Latvia and led by Pavel Bermondt-Avalov. In October, fighting restarted when the West Russian Volunteer Army attacked Riga. Following the Latvian request to help, Estonia sent two armoured trains to aid repelling the German attack. Estonian army also remained to support the defence of Latvia against Soviets by defending the front north of Lake Lubāns.
Soviet Russia had been attempting to conclude a peace since the spring of 1919. On 25 April 1919, Hungarian Communists offered to mediate a settlement between the Bolsheviks and the Estonians, but Admiral Cowan threatened withdrawal of support to the Estonians unless they rejected the Hungarian offer. The Russians then publicly broached the subject of peace talks in a radio broadcast on 27 and 28 April. On 5 June the Estonian Commune was abolished. A subsequent broadcast by the Russians on 21 July led to the British journalist Arthur Ransome sounding out the Commissar for Foreign Relations Georgy Chicherin on the subject of peace talks. As a result, the Soviet government made a formal offer for negotiations on 31 August 1919. The Estonians accepted on 4 September, and delegations started talks on 16 September. Estonia then proposed to stop the negotiations until Latvia, Lithuania and Finland have agreed to participate in joint negotiations.
In the autumn, the Northwestern Army launched operation White Sword, a major effort to capture Petrograd. With the arms provided by Britain and France, and the operational support by the Estonian Army, Estonian Navy, and Royal Navy, the Northwestern Army began the offensive on 28 September 1919. Estonia supported the Northwestern Army due to the demands of the Entente. The Estonian forces made joint naval and land attacks against the Krasnaya Gorka fort, while the Estonian 2nd Division attempted to destroy bridges over the Velikaya River and the Estonian 3rd Division attacked towards Pytalovo. The Northwestern Army approached to 16 kilometres (10 miles) from Petrograd, but the Red Army repulsed the White Russian troops back to the Narva River. Distrustful of the White Russians, the Estonian High Command disarmed and interned the remains of the Northwestern Army that retreated behind the state border.
The 7th and 15th Soviet Armies advancing behind collapsing White Russian forces continued to attack the fortified positions at the state border near Narva. First clashes took place on Luga River on 16 November, starting the conclusive battles with 120,000 Soviets facing 40,000 Estonians. After repeated attacks, the 7th Red Army managed to achieve some limited success. At the end of November the situation on the front calmed, as the Soviets needed to replenish their forces. In order to pressure Estonia in the peace talks, intensive Soviet attacks restarted on 7 December. On 16 December, the situation became critical as forward units of the 15th Red Army crossed the Narva River. The next day, an Estonian counterattack pushed the Soviets back. The Estonian high command actively reinforced the 1st Division at Narva during the battles, sending in the headquarters of the 3rd Division. General Tõnisson became commander of the Viru Front. After suffering 35,000 casualties in heavy battles, the Red Army was completely exhausted by the end of December.
On 19 November, the new government of Jaan Tõnisson decided to restart talks with Soviet Russia, even without the participation of other Baltic States. Negotiations began on 5 December, with the main point of dispute being territorial issues. Talks continued through December, with both sides pressing their territorial demands, while heavy fighting continued at Narva. The peace treaty was finally concluded on 31 December 1919, and the ceasefire came into effect on 3 January 1920.
Foreign assistance, mostly from the United Kingdom and Finland, played a very important role during the early stages of war.
British naval and air forces arrived in December 1918, after lobbying in London by Estonian politicians. The British squadron delivered 6500 rifles, 200 machine guns, 2 field guns, also two Soviet destroyers were captured near Tallinn and turned over to Estonia. A Royal Navy squadron continued to provide artillery support on the coast and also protected the Estonian flank against the Russian Baltic Fleet. The United Kingdom remained Estonia's main supplier of arms and equipment during the war.
While the British navy provided considerable support, the historian William Fletcher concludes that "the British naval force would have had little effect on the outcome of Baltic affairs had not the Estonians and Latvians provided a vibrant and disciplined land and sea force".
Finland provided 5000 rifles and 20 field guns by 12 December. Finland also sent 3500 volunteers. Pohjan Pojat led by Hans Kalm fought at the Southern Front, including at the Battle of Paju, while I Suomalainen Vapaajoukko led by Martin Ekström fought at the Viru Front, including at the Battle of Utria. Finnish volunteers returned to Finland on March–April 1919, having lost 150 men.
Danish-Baltic Auxiliary Corps with approximately 200 men was formed under the command of Captain Richard Gustav Borgelin in April 1919. The company took part in battles against Bolsheviks in Latvia and near Pskov and 19 men were killed by the time their contract ended in September. R. G. Borgelin was promoted to Lieutenant Colonel and given Maidla manor in gratitude for his services.
The Swedish volunteer unit under the command of Carl Mothander was formed in Sweden in early 1919. In March 1919, 178 volunteers took part in scout missions in Virumaa. In April, the company was sent to the Southern front and took part of the battles near Pechory. In May, the company was disbanded with some volunteers joining other units and the rest returning to Sweden.
On February 2, 1920, the Peace Treaty of Tartu was signed by the Republic of Estonia and RSFSR. At this point, the Bolshevist regime had not been recognized by any Western power. The terms of the treaty stated that Russia renounced in perpetuity all rights to the territory of Estonia. The agreed frontier corresponded roughly with the position of the front line at the cessation of hostilities. In particular, Estonia retained a strategic strip to the east of the Narva river (Narvataguse) and Setumaa in the southeast, areas which were lost in early 1945 – shortly after Soviet troops had taken control of Estonia, when Moscow transferred the land East of the Narva River and most of Petseri County to the RSFSR.