Baker was born to an English father and Scottish mother[3] in New Rochelle, New York, where they were settled at the time.
In 1939, his parents moved for a short while to Liverpool, where Gerry's brother, future England international Joe Baker, was born.
Their father volunteered in the Merchant Marine during World War II and died on active service.
[4][6] He scored the winning goal for St Mirren on his debut, a 2–1 victory against a Hibernian team containing his brother Joe.
[6] By this time, top English clubs were beginning to notice and in November 1960, Manchester City paid £17,000 for him[6] (the deal also involved defender John McTavish moving in the opposite direction).
[7] Baker held dual US and British citizenship, and when it became apparent that he would not be selected for Scotland or England,[citation needed] he elected to make himself available for the US team.
Over the next month, Baker started six games with the US on 2 November 1968, he scored two goals in a 6–2 qualification victory over Bermuda.
[citation needed] In 1970, Baker entered the managerial ranks at Margate when he was hired as the club's player-manager.
[citation needed] After retiring from playing professionally, Baker worked at the Coventry Jaguar factory.