Carlo I Malatesta (June 1368 – 13 September 1429) was an Italian condottiero during the Wars in Lombardy and lord of Rimini, Fano, Cesena and Pesaro. He was a member of the powerful House of Malatesta.
Carlo was the brother of Pandolfo III and Andrea Malatesta, with whom he fought in numerous occasions.
In 1385 he was named vicar for Romagna by the Pope Urban VI and, two years later, Gonfalonier.
In 1390 he defeated a Bolognese corps led by Alberico da Barbiano. In his early years he fought mainly against the Montefeltro family, but later allied with them through a double marriage arrangement.
In 1397 he was named commander of the Anti-Visconti League, formed with Florence and Venice, as well as his traditional ally, the Papal States. In 1401, when his brother Pandolfo left for the Holy Land, Carlo passed under Gian Galeazzo Visconti of Milan, defeating the Florentine army at the siege of Brescia, personally capturing in a duel Leopold of Austria. Later he was against the Visconti, leading a Papal army against Bologna.
In 1406 he was named governor of Milan, but his loyalty lasted for only one year. From 1409 Carlo fought constantly for the Papal States, not only as Captain General of the Church but also as diplomat. In the chaotic situation created by the presence of three popes at the same time, he backed Gregory XII, whom he also housed in his lordship in Rimini, until his abdication at the Council of Constance. The resignation letter was read by Carlo himself.
In 1412 the became capitano generale (commander-in-chief) of the Venetian army, fighting against the Hungarian invasion of King Sigismund. However, he was wounded in action at the Battle of Motta, and had to cede his position to Pandolfo.
On 12 July 1416 Malatesta was defeated by Braccio da Montone at the Battle of Sant'Egidio, wounded and taken prisoner. Pandolfo paid 80,000 ducati as ransom. Later, his territories were invaded by the Visconti army. Carlo lost Forlì and Gradara, and was subsequently defeated at Zagonara. Again taken prisoner, he was housed as a guest by the Duke of Milan Filippo Maria, and later freed without harm.
Carlo's wife was Elisabetta Gonzaga; they were married in November 1386. The Carlo Malatesta who married Vittoria Colonna, niece of Pope Martin V, was the son of Malatesta dei Sonetti who was lord of Pesaro. Guillaume Du Fay's Ballade "Resvellies Vous" (Awake and be merry) was written for the marriage of this younger Carlo in 1423. Carlo Malatesta of Rimini provided the newlyweds with a "most sumptuous nozze" in Rimini.
Malatesta died in 1429, having obtained by Pope Martin V the legitimation of his sons, who inherited the seigniories of Rimini and Fano, while the sons of Malatesta dei Sonetti received Pesaro and his nephew Domenico received Cesena.