How did coffee cultivation spread from Ethiopia to Yemen?

Wild coffee plants (Coffea species) are believed to be native to the Kefa (Kaffa) region of Ethiopia. While the exact history of their domestication remains unclear, tradition holds that coffee plants were transported across the Red Sea to southern Arabia (modern-day Yemen) by the 15th century.213

One prominent tradition suggests that a Sufi mystic or leader of a religious order discovered the stimulating properties of the coffee berry and brought the practice of coffee drinking to Arabia. Sufi monks are often credited with being among the first to brew coffee as a beverage, utilizing its stimulating effects to aid in their nocturnal prayers. Once established in Yemen, the plant was placed under cultivation, and the port town of Mokha eventually became the primary center for the coffee trade, maintaining a monopoly on the supply until the 17th century.4521