Angelica Pickles is a mysterious member of a mysterious group of a mysterious country of a mysterious world of a not so mysterious universe. In other words, she's some brat that was chosen to join the Nazi special task force known as the Rugrats. She was chosen both for her relation to Tommy and Stu Pickles, and for her dark depressing soul. She is also one of the driving factors that caused Stu Pickles to lose control of his life.
Angelica Pickles was born to the brother of Stu Pickles in 1804. For the first four years of her life, she made her parent's life Hell by being a little stuck up brat. Even when she was only three days old, she managed to steal cookies out of the cookie jar. Her special operations skills were unprecedented for someone under a week old. These skills only improved as she grew.
In 1808, Vendetta Williams realized war was bound to happen soon. To prepare Germany, she gathered several Nazi babies and cast a spell on them to keep them babies forever. Angelica was too old to join at four years old, but Williams eventually included her in the group anyways. After another four years, the War of 1812 broke out.
Angelica served directly under her younger cousin Tommy Pickles. When the Rugrats were deployed into New York, Angelica was the one in charge of screaming at the enemy for no particular reason. Half way into the battle she saw American soldier Michael Jackson and retreated because she was so scared. She later claimed that she scared Jackson away, but we all know that's crap.
She continued fighting the Americans and then the Antarcticans in the War of 1812. Though she had no combat role and wasn't even given a weapon, she somehow managed to defeat more enemy soldiers than Tommy did. This made Tommy jealous, so Angelica did not get her promotion. She vowed revenge.
The importunity for revenge came about a hundred years later. She had returned to the small village on the outskirts of Berlin that she and Tommy were native to. All of the citizens ran for safety when the realized the infamous Angelica had returned. She marched down the street like you would expect in some cheesy western movie. There she took a massive dump
After years of horrific torture, Stu finally began to follow the path that would ultimately lead to a family ruined. Angelica, pleased with her work, left to go into hiding somewhere in UnAmerica. She stayed in hiding until the War of 2012, when she returned to fight with the Germans. She did not, however, regroup with the Rugrats. After the War of 2012, Angelica went back into hiding. Her injuries from the war caused her to remain inactive for the rest of her immortal life.
Well, except for when Bob Saget took her to Evil Island under the alias of "Hiyoko Saionji", where she befriended "Mahiru Koizumi", but failed to make any other meaningful connections before her throat was slit.