Who was Batman's first accomplice?

Right from the off, Batman's first and foremost accomplice was Alfred Pennyworth. If you mean partner in crime-fighting, then that was Dick Grayson, Robin I. Stephanie Brown took the mantle of Robin very briefly before Dick reclaimed it. Then it was Betty Kane, the first official Bat-girl. Then came Barbara Gordon, Batgirl II. Then Grayson left and for a brief time Jason Todd became Robin II. Then, Tim Drake took over as Robin III. Cassandra Caine now acts as Batgirl III. Dick Grayson is now Nightwing, Barbara is known as Oracle, Stephanie became Spoiler and Betty Kane acts as Grayson's sidekick Flamebird.