“A History of Ancient Rome” by N.A. Mashkin is arguably among the most comprehensive and full sources on Roman history, starting pre-Roman era till the conventionally accepted date of the Fall of the Roman empire (and even expanding the discussion of consequences a bit further).
Introductory paragraphs to each chapter might be selectively read first: to get the whole picture of the events before plunging into abundant details.
English title: N.A. Mashkin “A History of Ancient Rome”
Original title (Russian): Н.А. Машкин “История Древнего Рима”
First published in the Levinarium Telegram Channel (now closed and deleted)