Archibald Campbell, 5th Earl of Argyll (1532/1537 – 12 September 1573) was a Scottish nobleman, peer, and politician. He was one of the leading figures in the politics of Scotland during the reign of Mary, Queen of Scots, and the early part of that of James VI.

Succeeding his father Archibald Campbell, 4th Earl of Argyll (c. 1507–1558) in the earldom in 1558, Argyll's inheritance made him one of the most powerful magnates in the kingdom. A devout Protestant, he along with his brother-in-law, Lord James Stewart, illegitimate son of James V of Scotland, became an adherent of John Knox about 1556. Like his father he was one of the most influential members of the party of religious reform, signing what was probably the first "godly band" in December 1557, and Argyll soon became one of the leaders of the Lords of the Congregation.^[1] Together, Argyll and Stewart negotiated with Sir William Cecil to secure English aid against the regent, Mary of Guise, and were largely responsible for the negotiation of the Treaty of Edinburgh in 1560, which saw the triumph of the Congregation and the withdrawal of French and English troops from Scotland.^{[citation needed]} . It was about this time that Cecil referred to Argyll as "a goodly gentleman universally honoured of all Scotland."^[1]

Argyll, in his role as Campbell clan chief, was also heavily involved in the politics of Ulster during the 1560s. Although he initially hoped for an alliance with the English to secure his claims on land possessed by the O'Donnell and Sorley Boy MacDonnell families against the encroachment of the O'Neill, English unwillingness to work with him led him to orchestrate a marriage alliance among the three feuding clans of Ulster, which would ultimately have major effects on Irish history with the eruption of the Hugh O'Neill rebellion in the 1590s.

He first married Lady Jean Stewart (died 1588), daughter of James V of Scotland and Elizabeth Bethune; he was thus half-brother-in-law to Mary and to Moray. After divorcing Jean Stewart, Argyll married Jean Cunningham, daughter of the Earl of Glencairn in August 1573. Janet Cunningham gave birth to the Earl's stillborn posthumous son in June 1574.^[4] She subsequently married Humphrey Colquhoun of Luss and died in 1585.^[5]

Argyll died in September 1573, without male issue, and was buried at Kilmun Parish Church. He was succeeded by his half-brother Colin.

• Jane Dawson. The Politics of Religion in the Age of Mary, Queen of Scots: The Earl of Argyll and the Struggle for Britain and Ireland. Cambridge, 2002.