Phoenician lamed — "ox-goad", through Greek lambda.
L
an ox-goad is a stick with a point, used to drive cattle. The bend of the L is where the point was. Greek lambda stood it upright as Λ; Latin laid the foot flat, and that flat foot is the only difference between the two.
Aguilar · Allen · Alvarez · Arnold · Bailey · Bell · Black · Bradley · Butler · Campbell · Carroll · Castillo · Chandler · Clark
In the modern alphabet this letter is number 12 of 26. Before it comes K, after it M. 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 9 and closes 10. Among the 96 given names in the base it appears in 31. The surname carrying the most of it is Allen, with 2.
Michael · William · Charles · Daniel · Paul · Nicholas · Samuel · Alexander · Liam · Oliver · Lucas · Elizabeth
These letters came from the Greek alphabet.