Kings traced their descent from Cináed mac Ailpín, and not from his father, and Irish genealogies in the Book of Ballymote and the Book of Lecan refer to the kindred as Clann Cináeda meic Ailpín, prioritising descent from Cináed.^[1]

The origins of the family are uncertain. Later genealogies of doubtful reliability make Cináed a descendant of Áed Find. While plausible, such claims are unprovable and appear only in the late tenth century.^[2] The associated idea that Cináed had been a king in Dál Riata before contending successfully for power in Pictland in the 840s, following the death of Eóganán mac Óengusa, is supported by near-contemporary evidence.^[3]

Early kings of Clann Cináeda meic Ailpín are described as kings of the Picts, and the third king, Constantín mac Cináeda appears to have been regarded as the last of the seventy Pictish kings soon after his death. The descendants of Cináed were ousted in 878 when Áed mac Cináeda was killed by Giric mac Dúngail. They returned in 889 on the death of Giric. Following this, the title king of Alba is used.^[4]

During the tenth century, succession alternated between the descendants of Constantín mac Cináeda and those of Áed mac Cináeda. Internecine strife in the late tenth and early eleventh centuries left the descendants of Constantín unchallenged by male-line descendants of Cináed mac Ailpín, but Máel Coluim mac Cináeda left no male heirs. On Máel Coluim's death, the line of kings descended from Cináed came to an end. Future kings, while still tracing their descent from Cináed, were descended from Máel Coluim's daughter Bethóc.^[5]

See also: List of Kings of the Picts

The reign of Kenneth MacAlpin begins what is often called the House of Alpin, a concept entirely modern. The descendants of Kenneth MacAlpin were divided into two branches; the crown would alternate between the two, the death of a king from one branch often hastened by war or assassination by a pretender from the other. Malcolm II was the last king of the House of Alpin; in his reign, he successfully crushed all opposition to him and, having no sons, was able to pass the crown to his daughter's son, Duncan I, who inaugurated the House of Dunkeld.

† Giric and Eochaid have uncertain dynastic status, but do not appear to be direct members of the House of Alpin: Eochiad was a son of Run, King of Strathclyde, but his mother may have been a daughter of Kenneth I; Giric's family is unknown, although he may also have been related to the House of Alpin.