The Chicago Cubs baseball club is an original member of the National League (1876 to date), established in 1874 or 1870. Here is a list of players who appeared in at least one regular season game beginning 1874.
(Their 1870–1871 players are in Category:Chicago White Stockings players among many others to about 1890.)
Bold identifies members of the National Baseball Hall of Fame.
Italics identify players with uniform numbers retired by the team.
References
Chicago Cubs all-time roster Wikipedia(Text) CC BY-SA