Sir Robert Sidney (1563-1626) was an English courtier, soldier, and poet, known for his connections to the prominent Sidney family. He was the brother of the famous poet Sir Philip Sidney and served in various military campaigns, including those in the Low Countries. In addition to his military career, Robert Sidney was also a patron of the arts and contributed to the literary culture of his time. He held several important positions, including the governorship of Flushing in the Netherlands, and was involved in diplomatic missions, reflecting his influence in both military and political spheres.