a supreme headquarters
... that the Central Powers brought their armies under a supreme headquarters in September 1916, 18 months before the Allies did the same?
... that the <a href="./Central_Powers" id="mwBP8" rel="mw:WikiLink" title="Central Powers">Central Powers</a> brought their armies under <b id="mwBQA"><a href="./Supreme_War_Command" id="mwBQE" rel="mw:WikiLink" title="Supreme War Command">a supreme headquarters</a></b> in September<span id="mwBQI" typeof="mw:Entity"> </span>1916, 18 months before the <a href="./Allies_of_World_War_I" id="mwBQM" rel="mw:WikiLink" title="Allies of World War I">Allies</a> did the same?