"The Consummation of Empire" by Thomas Cole. Source: Explore Thomas Cole at https://tinyurl.com/y8mkcnrf.
The main factors that cause empires to decline are economic issues, social and cultural issues, political issues and environmental issues.
By now, you have learned about several major empires. Just to review, the term empire refers to a central state that exercises political control over a large amount of territory containing many diverse groups. Often, this centralized power rules from one or several capital cities. We usually refer to an empire as if it were a single unit. But, because empires are so large, they are often divided into smaller, more manageable political units, usually called provinces.
Source: Khan Academy
Google Scholar is a source of scholarly sources on the open web. Not everything is available this way, but sometimes Google Scholar can provide free, online access to things not available full-text in library databases. It's worth checking out!
BBC History Site
There are great resources here..
The Ancient Web
Lots of information is provided here. Use the menu on the left.
Internet Ancient History SourceBook, Good round-up of ancient sources availble online
Ancient / Classical History
This is a good starting point to build your knowledge. You can search for the site or browse to it by topic.
Ancient Civilisations
Ancient China shows up first but there are links to other civilisations along the top of the screen. Follow the links to find what you need.
Ancient History by Time Period - lots of useful links
Ancient Egypt at the British Museum
Ancient Greece at the British Museum
The Seven Wonders of the Ancient World
Stone Pages
Stonehenge, stone circles, dolmens, ancient standing stones, cairns, barrows, hillforts and archaeology of megalithic Europe.
Indiari and the Golden Skull, Artifact Hunter game
Jo Wilder and the Capitol Case game (artifacts, interactive)
Tools of the Trade - Solve this archaeology mystery
Archaeology Terms - Hangman, interactive
Archaeology "Who wants to be a millionaire" - Quia
Becoming an Archaeologist - Quia, several
Ancient Coins match game, interactive
Archaeology Flash Cards, quizlet
Archaeology Jeopardy (Jeopardy Labs)
Archaeology Q&A Quiz Interactive