As soon as Alexis Sanchez's move to Manchester United was in motion, Aubameyang emerged as a top target for the North London outfit.
Lengthy negotiations began, but the two clubs struggled to agree on a fee, with the Gunners initially having a reported £50m offer rejected.
The North London outfit managed to get a deal over the line on transfer deadline day, and widespread reports have claimed that the fee is in the region of £60m.
Aubameyang arrives at the Emirates with plenty of promise, having scored 98 goals in 144 competitive matches for Dortmund across five years.
This season, the forward, who will be reunited with ex-Dortmund teammate Henrikh Mkhitaryan, has scored 21 goals in 24 appearances in all competitions.