The foundation of the Kingdom of Hungary: Hungary is established as a Christian kingdom by Stephen I of Hungary.

1000 (M) was a leap year starting on Monday of the Julian calendar, the 1000th year of the Common Era (CE) and Anno Domini (AD) designations, the 1000th and last year of the 1st millennium, the 100th and last year of the 10th century, and the 1st year of the 1000s decade. As of the start of 1000, the Gregorian calendar was 5 days ahead of the Julian calendar, which was the dominant calendar of the time.

The Kingdom of Hungary was a monarchy in Central Europe that existed for nearly a millennium, from 1000 to 1946 and was a key part of the Habsburg monarchy from 1526-1918. The Catholic kingdom emerged as a continuation of the Grand Principality of Hungary upon the coronation of the first king Stephen I at Esztergom around the year 1000; his family led the monarchy for 300 years. By the 12th century, the kingdom had become a European power.

Stephen I, also known as King Saint Stephen, was the last grand prince of the Hungarians between 997 and 1000 or 1001, and the first king of Hungary from 1000 or 1001 until his death in 1038. The year of his birth is uncertain, but many details of his life suggest that he was born in, or after, 975, in Esztergom. He was given the pagan name Vajk at birth, but the date of his baptism is unknown. He was the only son of Grand Prince Géza and his wife, Sarolt, who was descended from a prominent family of gyulas. Although both of his parents were baptized, Stephen was the first member of his family to become a devout Christian. He married Gisela of Bavaria, a scion of the imperial Ottonian dynasty.