From Wikipedia:

J was originally an alternative version of I. There was an emerging distinctive use in Middle High German. Petrus Ramus (d. 1572) was the first to explicitly distinguish I and J as representing separate sounds.

I understand mose people haven’t heard of this Petrus Ramus. I haven’t either. Still, there is a ‘j’ hidden in my name, where it joins forces with the ‘i’ just before it and is guarded by the ‘n’ behind it. I know that the ij-combination (actually, it’s kind of a single letter) isn’t very well known, so I can understand that English people don’t know how to pronounce it. Except that they do know, or pretend to, and almost everyone I meet calls me Martin. Which is, actually, very badly wrong.

Because I’m too shy to correct people (and would be too awkward if I tried to), there we go: 1. the emphasis in Martijn is on the second syllable; 2. it rhymes to wine and 3. it doesn’t really rhyme to wine, so if you want to do very well, make it sound a bit closer to veign. Just so you know.

(I got an email today in which my name was spelled in three different ways. All three were wrong…)