Well, the various major 18th century conflicts started in the following years...(major ones highlighted)
1700: Great Northern War (ended 1721, but various further Russo-Swedish wars occur throughout the century)
1701: War of Spanish Succession (Marlborough etc.) (various conflicts continue until about 1727)
1733-38: War of the Polish Succession
1735-39: Russo-Turkish War
1739-42: Anglo-Spanish War (War of Jenkins' Ear) merging into...
1740-48: War of Austrian Succession (Frederick the Great etc.)
1745-46: last Jacobite rebellions
1754-63: Seven Years' War (inc. French and Indian Wars, Carnatic War, Third Silesian War)
1768-1774: Russo-Turkish War (again!)
1775-1783: American War of Independence
1787-1792: Russo-Turkish War (Austria join in as well this time)
1789-1799: French Revolution, leading to the Napoleonic Wars.
While I realise (and hope) that there's going to be more to this project than wars and battles, political intriguing and war are never going to be too far away, so something based around one or more of these would be sensible.
EDIT: Double Post, sorry...
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