The first-principles SIC-LSD theory is utilized to study electronic, magnetic and orbital phenomena in LaMnO₃. The correct ground state is found, which is antiferro orbitally ordered with the spin magnetic moments antiferromagnetically aligned. Jahn-Teller energies are found to be the largest energy scale. In addition, it is the Jahn-Teller interaction which is the dominant effect in realizing orbital order, and the electronic effects alone do not suffice.