Here are some links to a range of views on imperialism, starting with Hobson (1902) and Lenin (1916) and then onwards.
John A. Hobson (1902) Imperialism, A Studyhttps://www.marxists.org/archive/hobson/1902/imperialism/index.htm
Vladimir Ilyich Lenin (1916) Imperialism, the Highest Stage of Capitalism https://www.marxists.org/archive/lenin/works/1916/imp-hsc/
Samir Amin (2015) Contemporary Imperialism.https://monthlyreview.org/2015/07/01/contemporary-imperialism/
John Smith (2019) on imperialism https://mronline.org/2019/03/19/john-smith-on-imperialism-part-1/