Final answer:
George Gershwin and Ira Gershwin premiered the European version of Porgy and Bess.
Step-by-step explanation:
The European version of Porgy and Bess was premiered by George Gershwin and Ira Gershwin. They were the composers and lyricists of the musical. The premiere took place in London on October 9, 1935. The American cast, including Todd Duncan as Porgy and Anne Brown as Bess, also traveled to Europe to perform in the production.