Speaking of which,

Johann von Heinsberg is cool. Doing further research on him now, and apart from varying genealogical elements (placing his birth between 1360-1384, realistically at about 1370 seeing as he married at about 1390) I came across a site belonging to the archery guild of Heinsberg, who have been in existence for over 600 years. They were founded by no less than good ol' Johann, and are named after saints Gangolfus and John of Nepomuk (the latter obviously picked in honour of the lord of Heinsberg). Readers of this blog will now, no doubt, be surprised as this is the first medieval archery guild I have mentioned thus far not named after either saint Sebastian or saint George! Apparently there were no laws against not naming your archery guild after these two saints after all.

Ironically, five months after the citizens of Heinsberg had been granted their guild, complete with special rewards such as material for making clothes for winter and summer, they were already called upon to serve their lord in battle. They fought, and many died, at the battle of Monschau (1400) against the abbot of Stavelot.

Apart from that, information is varied. For example, Heinsberg is listed as lord of many territories, which, apart from Heinsberg, obviously, include Millen (in Brabant), Loon (part of Liège), Jülich (a separate duchy which he certainly did not control, but had rights to, which the duke of Guelders/Jülich bought off at a date unknown to me) and a host of smaller territories. I don't think any of these lands, apart from Heinsberg, were actually in his possession at any time, and were merely claims, possibly temporary loans or stewardships. In any case, every source confirms that he was poor and had to make a living by making war.
Update: Heinsberg received Millen as hereditary land from the duke of Brabant in 1420.

What can I say, I like the man. He is also the only important historical character in my story who actually has his character rooted in history, rather than just his name.

Also, made me laugh:

The Key To Love für Heinsberg - Dating im Internet - Übersicht ...Die männliche Linie der Herren von Heinsberg starb mit Johann IV. im Jahr 1448 aus.

Apparently an internet dating site has lifted wikipedia information to give its site some more background info - but perhaps a subconscious message is hidden in the knowledge of the Heinsberg family dying out in 1448...