
Formulate an answer to this elaborate question: John III of Egmont, was first Count of Egmont, Lord of Baer, Lathum, Hoogwoude, Aarstwoude, Purmerend, Purmerland and Ilpendam, and Stadtholder of Holland, Zeeland and West-Friesland, in the Low Countries, stadtholder, is an office of steward, designated a medieval official, and then a what?


national leader
