The 26-year-old scored 54 goals in 89 appearances for the Citizens, joining in the summer of 2018 after spells with East Fife, Annan, Bonnyrigg Rose, Berwick Rangers, and Stirling Albion after coming through the youth ranks at Dunfermline.
Henderson’s tally of 39 goals in 47 games during his first season earned him the SPFL League Two player of the season award as well as the Tartan Boot prize for finishing the campaign as top scorer but he was dogged by injuries in the following two seasons.
His last appearance for City came in the League One play-off semi-final second leg against Dumbarton.
Speaking to the club’s TV channel Henderson said: “I had a great time at Edinburgh City and won awards that I will keep forever.
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"Scoring 54 goals in 68 starts is a great achievement and I couldn’t have done it without the other players and staff at the club.
"The fans were also great with me and that pushed me on even more.
"However, sometimes when new management comes in, plans and methods change and I had to go somewhere I felt part of the plans going forward.
"I wish the club nothing but success.”
The 20-year-old striker is the Capital club’s fourth summer signing following the arrivals of Lewis Kidd, James Hilton, and Callum Tapping.