[Mount Athos]

And Jomo Kenyatta declared that Kenya was a Republic on Republic Day in December 1963, not 1964.

You're wrong, Republic day for Kenya is Dec 12 1964, not 1963.

[Beloved Levinite]

Wiki:
Jamhuri Day is a national holiday in Kenya, celebrated on 12 December each year.[1] Jamhuri is the Swahili word for “republic” and the holiday is officially to mark the date of Kenya’s establishment as a republic on 12 December, 1964. However, the country also gained full independence from the United Kingdom one year earlier on 12 December, 1963, so Jamhuri Day is a double event and is generally regarded as Kenya’s most important holiday, marked by numerous cultural festivities which celebrate the country’s cultural heritage.

Jamhuri Day is often associated with Dedan Kimathi, the executed leader of the famous Mau Mau, regarded by many Kenyans as the hero who lifted the nation on his shoulders toward independence but he was executed before he completed his mision.

[Beloved Levinite]

Kenya’s a third world Banana Republic, more so in 1963. Whose to say they wouldn’t just start using Republic of Kenya on their govt docs after Kenyatta became President Banana & claimed their independence in Dec ‘63?

[Cicero]

It depends what authority you consult. Wikipedia says 1964. Other sources say 1963.