Mercury was born on the British protectorate of Zanzibar, East Africa (now part of Tanzania)
No one replaced him. In 2004, the "new band" Queen + Paul Rodgers was formed, in which surviving Queen members Brian May and Roger Taylor teamed up with vocalist Paul Rodgers- "It was made clear that Rodgers would not be replacing Queen's former lead singer, Freddie Mercury, who died in 1991, he would simply be 'featured with' former Queen members."
Freddie Mercury's partner Jim Hutton is still alive and living in Ireland.
Sadly, Jim Hutton, Freddie Mercury's lover at the time of his death passed away on January 1st 2010. May they both rest in peace.