Diageo was formed on 17 December 1997 through the merger of Grand Metropolitan plc and Guinness plc, two of the largest British consumer goods companies of the 20th century. The merger created the world's largest alcoholic beverages company at the time and was one of the largest corporate mergers in British history.
Grand Metropolitan plc was a British conglomerate that had assembled a portfolio of food, beverage, and hospitality assets over several decades. Its beverage brands included Smirnoff vodka, J&B Scotch whisky, Baileys Irish cream, and Malibu rum. Grand Metropolitan had also owned Burger King, which it sold in 1997 prior to the Diageo merger.
Guinness plc was the Irish brewing and spirits company that owned the Guinness stout brand, Johnnie Walker Scotch whisky, Bell's whisky, and a portfolio of other spirits brands. Guinness had itself been the subject of a major corporate scandal in the 1980s, when its chairman Ernest Saunders was convicted of fraud related to an illegal share-support operation during Guinness's 1986 takeover of Distillers Company.
The merged entity was named Diageo, a name derived from the Latin "dia" (day) and the Greek "geo" (world), intended to convey the company's global reach. Tony Greener, who had been chairman of Guinness, became chairman of Diageo, and George Bull, who had been CEO of Grand Metropolitan, became the first CEO of the combined company.
In 1998, Diageo sold its Pillsbury food business and its Burger King fast food chain to focus exclusively on alcoholic beverages. The divestitures were part of a strategic decision to concentrate on premium spirits and beer rather than operate as a diversified consumer goods conglomerate.
In 2001, Diageo acquired the Seagram spirits and wine portfolio from Vivendi Universal for approximately 8.15 billion US dollars, in a joint acquisition with Pernod Ricard. Diageo's share of the acquisition included Captain Morgan rum, Crown Royal Canadian whisky, Seagram's 7 Crown American blended whiskey, and several other brands. This acquisition significantly strengthened Diageo's position in North America.
In 2014, Diageo acquired a majority stake in Don Julio tequila from Patron Spirits for approximately 408 million US dollars, gaining full ownership of the brand. Don Julio has since become one of Diageo's fastest-growing brands, delivering double-digit growth in multiple consecutive years.
In 2015, Diageo sold its wine business, including the Blossom Hill and Beaulieu Vineyard brands, to Treasury Wine Estates for approximately 552 million US dollars, further concentrating the portfolio on spirits and beer.
In 2022, Diageo completed the acquisition of a 21% stake in Moet Hennessy, the wines and spirits division of LVMH, for approximately 2.5 billion US dollars, giving Diageo exposure to the Hennessy cognac brand and other LVMH beverage assets.
For the fiscal year ended 30 June 2025, Diageo reported net sales of approximately 20.2 billion US dollars, with organic net sales growth of 1.7%. Don Julio, Guinness, and Crown Royal were identified as standout performers. The company also announced an "Accelerate" cost savings programme targeting approximately 625 million US dollars in savings over three years.