Complex sentence: In 1908, Buckley moved to Mexico and established himself as a lawyer, founding the firm of Buckley & Buckley with his brother Claude Buckley to represent major American and European oil companies operating in Mexico.
Split into simpler sentences: In 1908, Buckley moved to Mexico and established himself as a lawyer. Together with his brother Claude, he founded the firm of Buckley & Buckley to represent major American and European oil companies operating in Mexico.