The newest princess born into the English monarchy is Princes Eugenie of York. She was born in 1990. Lady Louise Windsor was born in 2003 but she is titled as a lady not a princess.
The princess royal (princess anne)
Princess Anne is the firstborn daughter of the English monarch, and so is the current Princess Royal.
Princess Pingyang was born in 598.
Princess Tokushi was born in 1060.
Princess Teishi was born in 1013.
Princess Hwahyop was born in 1733.
Princess Taiping was born in 665.
Princess Teruko was born in 1224.
Princess Kaoruko was born in 1029.
Princess Tōchi was born in 653.
Princess Rym was born in 1969.
Princess Seishi was born in 810.