Phoenician qoph, through Greek qoppa and Etruscan.
Q
Greek eventually dropped this letter and kept it only as a numeral — but Latin had already taken it, through Etruscan, while it was still in use. Latin gave it one job, the combination QU, and English keeps it: outside borrowed words like Qatar and burqa, a q here is followed by a u.
In the modern alphabet this letter is number 17 of 26. Before it comes P, after it R. The order itself is inherited: Latin took it from Greek, Greek from Phoenician, and the sequence has survived largely unchanged for about three thousand years. Every rearrangement since has been an insertion, not a reshuffle.
This is a consonant: it sets the hardness of a name and how it meets the next word. In a corpus of 315 surnames this letter opens 1 and closes 0. Among the 96 given names in the base it appears in none — which is itself a fact about names. One occurrence per surname is the ceiling: no surname in the corpus repeats this letter.
These letters came from the Greek alphabet.