From Wookieepedia, the Star Wars wiki.
The Battle of Orto, fought primarily in the last week of the Clone Wars, was a Republic effort to remove Orto's illegal new Confederacy-aligned government.
The foundations of the battle were laid several months before the Republic's full assault. On intelligence that a government official on neutral Orto was plotting to join the Confederacy of Independent Systems, Jedi Nem Bees went under the guise of the deceased trader Ydde to the planet to root the traitor out.
Nem was too late, and when Financial Minister Belo Tusus announced his allegiance to the Confederacy, Bees posed as a scared citizen as battle droids swarmed the capital. For months he remained in hiding, engaging in acts of sabotage to hamper Confederacy efforts, until he obtained the chance to call in Republic forces.
and Ortolan civilians witness the invasion.
Bees proceeded to the Ortolan palace to destroy the planetary shield generator, thus allowing the forces, led by Commander CT-65/91-6210 (Deviss), to land. He then rendezvoused with Deviss and the K Company, and they began driving the entrenched droid army out of the system. One week later, Order 66 came through. While leading an assault force on enemy lines, Deviss and his squad cut down Bees. Orto was absorbed into Imperial control after the deactivation of the droids.
- Star Wars: Clone Wars – "Chapter 22" (First appearance)