Waldo Williams (1904-1971) was one of the leading Welsh language poets of the 20th century. He was also a notable pacifist, anti-war campaigner and Welsh nationalist. His poetry shows many influences, from William Wordsworth and Walt Whitman to Welsh hymns and traditional Welsh cynghanedd. Born in the Haverfordwest area, Williams moved to north Pembrokeshire with his family in 1911. He studied English at Aberystwyth University and taught in a number of Pembrokeshire schools, standing as the Plaid Cymru candidate for Pembrokeshire in 1959. Williams' work was touched by romanticism but also often carried a political message, directly influencing the emergence of the 1960s Welsh nationalist movement. He published one volume of poetry, entitled Dail Pren (Gwasg Aberystwyth, 1956), and another in collaboration with Llwyd Williams; Cerddi'r Plant (Gwasg Aberystwyth, 1955).