[11] The company expanded the tobacco growing enterprises in the United States that WD & HO Wills had developed before the amalgamation of 1901.

[13] Divestments during the period of ownership by Hanson included Courage Brewery to Elders, Golden Wonder to Dalgety, Finlays to Arunbhai J. Patel, the wholesaling arm of Sinclair & Collis to Palmer & Harvey, Imperial Hotels and Catering to Trust House Forte and Ross Frozen Foods to United Biscuits.

[15] In 2003, Imperial acquired the world's then fourth-largest tobacco company, Reemtsma Cigarettenfabriken GmbH of Germany: the deal added brands such as Davidoff, Peter Stuyvesant, and West to its portfolio.

[17] In February 2008, Imperial acquired the world's then fifth-largest tobacco company, Altadis, whose brands included Fortuna, Gauloises Blondes, and Gitanes.

[20] In 2011, Altadis USA Inc. said it would add to its Fort Lauderdale, Florida, headquarters and move Commonwealth Brands Inc. employees from Bowling Green, Kentucky.

[24] On 15 July 2014, Reynolds American agreed to buy Greensboro, North Carolina–based Lorillard Tobacco Company, for $27.4 billion.

[25] The deal also included the sale of the Kool, Winston, Salem, and blu eCigs brands to Imperial for $7.1 billion.

[28] On 1 November 2018, ITG announced production would move from the former American Tobacco Company plant in Reidsville, North Carolina, built in 1892, and later expanded, to Greensboro by 2020.

[30] In 2018, a subsidiary, Imperial Brands Ventures, took a stake in Oxford Cannabinoid Technologies which is licensed by the UK government to develop cannabis-based medicines.

[31] In November 2019, after searching for a new chairman since February, the company announced its senior independent director Thérèse Esperdy would take the role.

[4] In 2021 Imperial Brands launched the Pulze and iD heated tobacco system in selected European markets.

[35] The principal companies involved in setting up Imperial Tobacco were W. D. & H. O. Wills Limited and John Player & Sons of Nottingham.