Llywelyn ap Gruffudd was the last Welsh Prince of Wales.
How is this name pronounced?
More generally, can someone recommend a good resource for Welsh pronunciation guidance?
A double consonant softens the basic consonant sound.
The double L is sounded by putting the tip of your tongue up to your palate and sort of blowing round the sides.
W is a vowel, roughly “oo” in sound
U is more or less pronounced like the I in “ill”.
Double D represents the “TH” in “third”.
So roughly this is Hl-ew-elin ap Griffith.
Plenty of guides on Youtube: try https://www.youtube.com/watch?v=3bmPYl6ScNk
Roughly speaking: Hleewelin ap Grifith
http://www.namenerds.com/welsh/trad2.htmlThanks much!
One should be careful here with this set of answers, Bricker. Llewelyn ap Gruffydd lived in the 1200s. Just as English underwent a tremendous change in pronunciation between the mid-1300s and the 1600s (the Great Vowel Shift), so, too, might Welsh have undergone some changes in how things were pronounced. So using modern pronunciation rules might produce a completely incorrect way to say his name, from the standpoint of historical accuracy.
I can’t believe how long I have mispronounced Elmer Fudd 
An excellent point. I can’t speak for Bricker, but I, for one, will certainly proceed with caution should I find myself in conversation with a thirteenth century Welshman.
Go to Google Translate, enter the term in English, select translate to Welsh, click the little loudspeaker icon under the Welsh translation. In this case, you will get a synthesized voice, but for must languages, you will get a native speaker.
Not a Welsh speaker but I think dd represents the voiced th /ð/ as in “this” or “smooth”, not the unvoiced th /θ/ of “third”.
Or Roger Mudd (Mith) or Paul Rudd (rith).
Forvo is pretty good for these things, and this pronunciation from a local speaker seems legit to me. I don’t speak Welsh, but that initial sound for “ll” sounds like what I know the Welsh “ll” sound to be, so I’d venture it’s probably spoken by a native speaker.
Related question: The surname is often spelt with a double l in the middle, too, i.e. Llewellyn.
Is that pronounced [ɬəˈwɛɬɪn] with the double l sound in the middle, too, or is it just a spelling error that has been propagated down the centuries?
Indeed. Were he Welsh, you’d have to talk about Elmer Veeth.
The ‘Ll’ sound doesn’t occur in English, so it’s hard to describe. To my ears it sounds most like ‘khl’ at the start of a word, but more like ‘thl’ when there are other letters in front of it, e.g. if I had to render how ‘Llanelli’ sounds to me, I would say it sounds most similiar to ‘khlanethly’. That’s not to say it’s necessarily pronounced differently depending on position (Welsh spelling is mostly phonetic), but that’s how it sounds to me.
A digression/diversion: when that Icelandic volcano was all over the news, I learnt that the “ll” in Icelandic indicates a sound like a combination of a glottal stop + the Welsh “ll” - and that in its early days the country had been populated by Viking raids on Britain to find wives (or at least domestic slaves and babymothers), so I wondered if that’s where the sound came from.
Somewhat surprisingly, given how much smaller the number of speakers has always been, Welsh pronunciation seems to have changed very little since the 13th century. There’s nothing quite like the Great Vowel Shift known from surviving literature (as with contemporary English, we can deduce a lot about pronunciation from the nonstandard orthography of the day). The written language, on the other hand, has changed nearly as much as English has over the last 800 years.