Born in Coburg into the family ruling the German duchy of Saxe-Coburg-Saalfeld (now in Bavaria). Joined the Imperial Russian Army and fought Napoleon. On his defeat Leopold moved to London and married Princess Charlotte, but she died following a still-birth so his hopes of a powerful ruling role in Britain failed. He was offered the Greek throne but rejected it as risky. Following the 1830 revolution Belgium was seeking a King and Leopold reluctantly accepted the offer.
Leopold brokered the marriage of Victoria to his nephew, Prince Albert, and remained a strong influence on the Queen all his life. Father of Leopold II.
Died near Brussels where he also has some memorials.