What was the name of Columbus's brother who became governor of Hispaniola?

Columbus’s brother who became a governor-like official on Hispaniola was Bartholomew Columbus. He joined Christopher during the second voyage and was appointed adelantado, a senior-ranking colonial office often translated or described as governor.

Bartholomew had worked as a mapmaker in Lisbon and had helped Christopher develop the plan to reach Asia by sailing west. Before Christopher gained royal backing, Bartholomew unsuccessfully sought support from the courts of England and France. He reached Hispaniola in 1494, after Christopher had already departed Spain.

During Christopher’s absences, Bartholomew exercised authority over the colony. He also founded Santo Domingo between 1496 and 1498, a settlement that became the capital of the Dominican Republic and eventually replaced La Isabela as the principal Spanish base on the island.

The Columbus family produced several important colonial figures, which can cause confusion. Christopher’s brother Diego also held authority in Hispaniola, while Bartholomew’s title was specifically adelantado. Nevertheless, Bartholomew is the intended and historically defensible answer to this question.