When did the Chicago Colts become the Chicago Cubs?

Answer 1

The Cubs became an MLB team in 1871 as a charter member of the National Association. They were known then as the Chicago White Stockings.

Answer 2

The Chicago Colts was the name of the team from 1890 - 1897. They became the Chicago Orphans in 1898 and it wasn't until 1902 that the team became the Chicago Cubs.

Answer 3

1903.

Prior to that, the team was known as the Orphans (1898-1902), Colts (1890-1897), and White Stockings (1871-1889).