Fray Nicolás de Ovando had valid reasons to believe Santo Domingo was vulnerable to attack when he became governor in 1502. The riches from the gold rush of 1500 to 1508 had attracted the attention of potential French and British conquerors plus pirates. The enslaved indigenous Taíno people were increasingly combative as their population shrank from disease and abuse while working the mines. So he ordered the construction of Ozama Fortress. The initial citadel was finished in 1508. The 59 foot Tower of Homage was added in 1509. Torre del Homenaje became the temporary residence of Diego Columbus (eldest son of Christopher) when he was appointed Governor of the Indies in the same year. Throughout most of the ensuing 500 years, Ozama Fortress was a prison. Many political adversaries were incarcerated and executed here until the 1960s.