The first record of the Cawdor family is found in 1295, when Donald, the first thane, was listed as juror at the Nairn assize. In 1310 his son, William, was granted a charter of hereditary thanage, rendered for political services to King Robert I. Thanage was a dedicated geographical area, and the thane held powers, particularly judicial and financial powers, over those residing within its border, giving the thane real consequence locally. The thanes of Cawdor were eager to enhance their power further, and did so by acquiring land. Almost the only record of the early thanes, from Donald onwards, is of their land transactions: land acquisition, then and for centuries to come, was inextricably linked with the pursuit of political power, both locally and in the national arena. To varying degrees, whilst obeying the vagaries in the ebb and flow of economic reality, the pursuit of land was undertaken by the Cawdors into the twentieth century.
The continued expansion of Cawdor land possessions in the fourteenth and fifteenth centuries attracted the interest of the land-greedy chiefs of the clan Campbell, the earls of Argyll, who were seeking to expand their influence eastward. When John, the eighth thane of Cawdor died in 1498, he left two underage heiresses, and the second earl of Argyll saw an opportunity. When Janet, the eldest girl, died, her sister Muriel, who was about nine years old, became the ninth thane of Cawdor, and Argyll's prime target. He abducted her, and in 1510 married her to his third son, Sir John, when she was about twelve years old. Thus, the thanes of Cawdor became inextricably linked with the clan Campbell.
Sir John Campbell sought ‘incessantly to increase his possessions and extend his influence’ and acquired great power in the north of Scotland, so much so that the Campbells of Cawdor almost came to rival their clan chiefs, the Argylls. However, Sir John died in 1546, leaving Muriel as head of the Cawdor estate, a position she maintained until 1573, when, two years before her death, she granted the thanedom to her grandson, John Campbell, her eldest son Archibald having died in about 1551.