Former Okinawa Gov. Masahide Ota, a noted historian and survivor of the Battle of Okinawa, died Monday of pneumonia and respiratory failure at a hospital in Naha, his office said. He had turned 92 the same day.

Ota, head of the Okinawa International Peace Research Institute, served as governor from 1990 to 1998. He was governor when U.S. Ambassador Walter Mondale agreed with Prime Minister Ryutaro Hashimoto in April 1996 to return the land used by the Futenma air base in Ginowan, central Okinawa.

The accord was aimed at reducing the U.S. military's footprint in Okinawa, which hosts the bulk of its military facilities in Japan.