Eighty.

This is coolbert:

Consider this to be the first world war? A world war as fought by the combatants on a world-wide scale at least, hardly confined to strictly the European political and cultural domain!

The Eighty Years' War. Dutch versus Spain. Holland as a nation-state political not existing at the time but as rather as a collection of provinces with a unified [?] Dutch culture under foreign rule.

Too in a very vague fashion was I even aware of any of this. Thanks to Lew for the tip.

A war consisting of distinct stages. 

* First forty years. (1566–1609). Dutch revolt.
* Twelve Years' Truce. A hiatus but with much tension.
* Resumption of the war. Thirty Years War with Dutch participation.

"The Eighty Years' War . . . or Dutch War of Independence (1568–1648) was a revolt of the Seventeen Provinces of what are today the Netherlands, Belgium, and Luxembourg, as well as the French region of Hauts-de-France against the political and religious hegemony of Philip II of Spain, the sovereign of the Habsburg Netherlands . . . An end was reached in 1648 with the Peace of Münster (a treaty part of the Peace of Westphalia), when the Dutch Republic was recognized as an independent country "

By Velasquez one of the "Ten Famous Representations of Military History in Western Art". "The surrender of Breda"! Click on image to see a larger view of high quality. The man in brown in the center of the image is presenting the keys of the city to the victor.

A WAR TO A CERTAIN EXTENT WAGED ON A WORLD-WIDE SCALE. SPANISH COLONIES IN BOTH HEMISPHERE SUBJECT TO SUDDEN ATTACK BY DUTCH NAVAL INSURGENTS. THE HISTORIANS I WOULD THINK HOWEVER HARDLY RECOGNIZE THIS PHENOMENA AS DESCRIBING A WORLD-WAR.

coolbert.