The Right Reverend Thomas Andrew Becker, sixth Bishop of Savannah, a convert from Protestantism, was consecrated first Bishop of Wilmington, Delaware, on August 16, 1868.

Bishop Becker was regarded as one of the most accomplished bishops in the United States. His series of articles on the idea of a Catholic university attracted wide attention. He was devoted to the temperance movement. Pope Leo XIII transferred Bishop Becker from Wilmington to Savannah on March 26, 1886. Before he completed the Cathedral with the building of spires in 1896, he had added the episcopal residence adjoining the Cathedral in 1889. On February 6, 1898, the Cathedral caught fire and was nearly destroyed. Savannah Catholics threw themselves into rebuilding the Cathedral. Bishop Becker solicited funds from his brother bishops. The work of rebuilding went on, despite a delay caused by the Spanish-American War. Bishop Becker died on July 29, 1899.