Stephen was born in the County of Blois in central France; his father, Count Stephen-Henry, died while Stephen was still young, and he was brought up by his mother, Adela, daughter of William the Conqueror. Placed into the court of his uncle, Henry I of England, Stephen rose in prominence and was granted extensive lands. He married Matilda of Boulogne, inheriting additional estates in Kent and Boulogne that made the couple one of the wealthiest in England. Stephen narrowly escaped drowning with Henry I's son, William Adelin, in the sinking of the White Ship in 1120; William's death left the succession of the English throne open to challenge. When Henry I died in 1135, Stephen quickly crossed the English Channel and with the help of his brother Henry of Blois, a powerful ecclesiastic, took the throne, arguing that the preservation of order across the kingdom took priority over his earlier oaths to support the claim of Henry I's daughter, the Empress Matilda.
The early years of Stephen's reign were largely successful, despite a series of attacks on his possessions in England and Normandy by David I of Scotland, Welsh rebels, and the Empress Matilda's husband, Geoffrey of Anjou. In 1138 the Empress's half-brother Robert of Gloucester rebelled against Stephen, threatening civil war. Together with his close advisor, Waleran de Beaumont, Stephen took firm steps to defend his rule, including arresting a powerful family of bishops. When the Empress and Robert invaded in 1139, however, Stephen was unable to crush the revolt rapidly, and it took hold in the south-west of England. Captured at the battle of Lincoln in 1141, Stephen was abandoned by many of his followers and lost control of Normandy. Stephen was freed only after his wife and William of Ypres, one of his military commanders, captured Robert at the Rout of Winchester, but the war dragged on for many years with neither side able to win an advantage.
Stephen became increasingly concerned with ensuring that his son Eustace would inherit his throne. The King tried to convince the Church to agree to crown Eustace to reinforce his claim; Pope Eugene III refused, and Stephen found himself in a sequence of increasingly bitter arguments with his senior clergy. In 1153 the Empress's son, Henry FitzEmpress, invaded England and built an alliance of powerful regional barons to support his claim for the throne. The two armies met at Wallingford, but neither side's barons were keen to fight another pitched battle. Stephen began to examine a negotiated peace, a process hastened by the sudden death of Eustace. Later in the year Stephen and Henry agreed to the Treaty of Winchester, in which Stephen recognised Henry as his heir in exchange for peace, passing over William, Stephen's second son. Stephen died the following year. Modern historians have extensively debated the extent to which Stephen's personality, external events, or the weaknesses in the Norman state contributed to this prolonged period of civil war.
Stephen was born in Blois in France, in either 1092 or 1096. His father was Stephen-Henry, Count of Blois and Chartres, an important French nobleman, and an active crusader, who played only a brief part in Stephen's early life. During the First Crusade Stephen-Henry had acquired a reputation for cowardice, and he returned to the Levant again in 1101 to rebuild his reputation; there he was killed at the battle of Ramlah. Stephen's mother, Adela, was the daughter of William the Conqueror and Matilda of Flanders, famous amongst her contemporaries for her piety, wealth and political talent. She had a strong matriarchal influence on Stephen during his early years.
France in the 12th century was a loose collection of counties and smaller polities, under the minimal control of the king of France. The king's power was linked to his control of the rich province of Île-de-France, just to the east of Stephen's home county of Blois. In the west lay the three counties of Maine, Anjou and Touraine, and to the north of Blois was the Duchy of Normandy, from which William the Conqueror had conquered England in 1066. William's children were still fighting over the collective Anglo-Norman inheritance. The rulers across this region spoke a similar language, albeit with regional dialects, followed the same religion, and were closely interrelated; they were also highly competitive and frequently in conflict with one another for valuable territory and the castles that controlled them.