Mackensen-class battlecruisers
... that the four Mackensen-class battlecruisers were canceled according to the terms of the Treaty of Versailles in 1919?
... that the four <b id="mwGes"><a about="#mwt77" data-mw='{"parts":[{"template":{"target":{"wt":"sclass","href":"./Template:Sclass"},"params":{"1":{"wt":"Mackensen"},"2":{"wt":"battlecruiser"},"3":{"wt":"2"}},"i":0}}]}' href="./Mackensen-class_battlecruiser" id="mwGew" rel="mw:WikiLink" title="Mackensen-class battlecruiser" typeof="mw:Transclusion"><i>Mackensen</i>-class</a><span about="#mwt77"> battlecruiser</span>s</b> were canceled according to the terms of the <a href="./Treaty_of_Versailles" id="mwGe0" rel="mw:WikiLink" title="Treaty of Versailles">Treaty of Versailles</a> in 1919?