The Empire State
... that the true source of New York's official nickname, The Empire State, is not known?
... that the true source of <a href="./New_York_(state)" id="mwIBY" rel="mw:WikiLink" title="New York (state)">New York</a>'s <a class="mw-redirect" href="./List_of_U.S._state_nicknames" id="mwIBc" rel="mw:WikiLink" title="List of U.S. state nicknames">official nickname</a>, <b id="mwIBg"><a href="./Empire_State" id="mwIBk" rel="mw:WikiLink" title="Empire State">The Empire State</a></b>, is not known?