Ostoher (TA 222-TA 492) the seventh King of Gondor, took to the throne after the death of his father Anardil in TA 411. In TA 420, he renovated and extended Minas Anor (Minis Tirith) and began using it as his summer home. This became tradition to his successors. In the 490th year of the Third Age Gondor was invaded by Easterlings for the first time. Ostoher being two years from death and an old man, so his son Tarostar (later Romendacil 1) took of the defence of Gondor. The Easterlings were defeated in TA 500, eight years after Ostoher’s death.
Trivia– Ostoher is a Quenya word, that is believed to mean “City Lord”.