What is the oldest written source in this country that mentions this right?

Barbados

In 1950 universal adult suffrage was introduced in Barbados for all of 21 years of age and over. In 1963 the right to vote was extended to those having reached the age of 18 years old.

References:

History of the form of Government in Barbados: https://www.electoral.barbados.gov.bb/25104-2/

Voting Rights and Suffrage · Country sources (all rights) · Last edited 2024-03-17 · Edit on GitHub