Ray Allen Billington byl americký historik, který se zaměřil na historii americké hranice a amerického Západu. Stal se jedním z předních obránců "Frontier Thesis" Fredericka Jacksona Turnera v letech 1950 až 1970 a rozšířil obor historie amerického Západu. Byl spoluzakladatelem Western History Association v roce 1961.
When it appeared in 1949, the first edition of Ray Allen Billington's Westward Expansion set a new standard for scholarship in western American history, and the book's reputation among historians, scholars, and students grew through four subsequent editions. This abridgment and revision of the fifth edition focuses on the Trans-Mississippi frontier.
Recognized for its cultural significance, this work contributes to the foundational knowledge of civilization. Scholars have deemed it essential, highlighting its importance in understanding historical contexts and societal developments.