Llywelyn ap Gruffydd

• Llywelyn ap Gruffydd, more commonly known as Llywelyn ap Gruffudd, also known as Llywelyn Ein Llyw Olaf, Llywelyn the Last, Prince of Wales 1258–1282
• Llywelyn ap Gruffydd Fychan, wealthy Carmarthenshire landowner executed by Henry IV of England in punishment for his support of Owain Glyndwr's Welsh rebellion