The Statute of Westminster of 1275 was one of two English statutes largely drafted by Robert Burnell and passed during the reign of Edward I. Edward I had returned from the Ninth Crusade on 2 August 1274 and was crowned King of England on 19 August.^[6] His first Parliament was summoned for the quinzaine of the Purification on 16 February 1275 but was prorogued until the day after Easter on 22 April 1275, but did not meet until the week commencing 29 April or, according to Chronicle records, until the beginning of May, for unknown reasons.^[7] It met at Westminster, its main work being the consideration of the Statute of Westminster I, the agreement of new levies in Ireland and allowing the King to levy a new tax on wool.^[7] This was drawn up, not in Latin, but in Norman French, and was passed "by the assent of Archbishops, Bishops, Abbots, Priors, Earls, Barons, and [all] the Commonalty of the Realm, being thither summoned."^[1]

According to Yuen Yuen Ang, the statute replaced a previously communal regime of contract enforcement with one based on "individual responsibility, territorial law, the central administration of justice, and personal collateral."^[8]: 144

The Statute of Westminster I is composed of 51 chapters:

In the early history of the Lordship of Ireland, English statutes were often applied to Ireland.^[11] A 1285 writ authorised Stephen de Fulbourn, then Justiciar of Ireland, to apply there English statutes including Westminster I, Westminster II, Gloucester, and those of merchants.^[12] A 1320 act of the Parliament of Ireland (13 Edw. 2 c.2) readopted all these statutes.^[13] An act of Edward Poynings' 1495 session of the Parliament of Ireland adopted statutes "formerly made for the common weal" in England; later the Maintenance and Embracery Act 1634 adopted all English statutes dealing with champerty and maintenance and embracery. Many chapters of the 1275 English statute were repealed with respect to Ireland by the Statute Law (Ireland) Revision Act 1872.^[14] In the Republic of Ireland, the Short Titles Act 1962 assigned the short title "Distress Act 1275" to chapter 16 of the 1275 English statute, as adopted under the 1495 Irish act;^[15] and the short title "Maintenance and Champerty Act 1275" to chapters 25 and 28 of the 1275 English statute, as adopted under the 1634 Irish act.^[16] The Statute Law Revision Act 1983 repealed the whole of the 1275 English statute and the 1285 and 1320 Irish statutes.^[17]

• Statute of Westminster 1285
• Quia Emptores of 1290 is sometimes called the statute of Westminster III^[18]

• Text of the Statute of Westminster the First 1275 (c. 5) as in force today (including any amendments) within the United Kingdom, from legislation.gov.uk. - Chapter 5 of the Statute
• Danby Pickering, ed. (1762). "Statute of Westminster the First". The Statutes at Large: From the Magna Charta, to the End of the Eleventh Parliament of Great Britain, Anno 1761 [continued to 1806]. Vol. I. Cambridge: Joseph Bentham. pp. 74–107. Retrieved 25 August 2017.
• Berry, Henry F., ed. (1907). Statutes and ordinances, and acts of the Parliament of Ireland. Statute rolls of the Parliament of Ireland (in French and English). Vol. 1 : King John to Henry V. Dublin: HMSO. Retrieved 25 August 2017.

• Tomlins, Thomas Edlyne; Raithby, John (1810). Statute of Westminster 1275 [3 Edw. I. - A.D. 1275 Statute I]. The Statutes of the Realm: Printed by Command of His Majesty King George the Third; in pursuance of an Address of the House of Commons of Great Britain. Vol. I. London, Great Britain: Dawson of Pall Mall. pp. 26–39. OCLC 426777557. {{cite book}}: |website= ignored (help)