Samuel ben Meir Abulafia was one of the wealthiest and most influential Jews in 14th century Spain. He became the financial adviser for Pedro the Cruel of Castile (1350-69). When nobles tried to revolt against the king in 1354, Abulafia and other wealthy Jews supported him and were successful in putting down the revolt. He placed his family members in positions of financial power and influence.
Samuel ben Meir was a generous philanthropist. He provided monies to build a number of synagogues in Castile including the magnificent synagogue in Toledo, which stands today as a national landmark.
Besides being Pedro's treasurer and adviser, he also served as a diplomat between Pedro and Portugal.
Without warning, in 1360 Samuel ben Meir was arrested and tortured to death in prison. His lands and house were confiscated by the king. His house still stands; today it is the El Greco Museum.
Sources: Gates of Jewish Heritage