Complex sentence: Beatriz de la Cueva de Alvarado (1498?-September 1541) was a Spanish noblewoman who became the governor of the Spanish colony of Guatemala from July 1541 until September of that year.
Split into simpler sentences: Beatriz de la Cueva de Alvarado (1498?-September 1541) was a Spanish colonial offical. She served as the governor of the Spanish colony of Guatemala from July 1541 until September of that year.