Ulster-Scots studies and ecocriticism are two areas of literary criticism that have burgeoned in the late twentieth and early twenty-first centuries. This thesis provides an original contribution to knowledge by employing ecocritical methodologies to analyse UlsterScots poetry published between 1790 and 1850. This thesis adds to the awareness of UlsterScots literature as a transcultural form ofIrish and Scottish writing. It also demonstrates that interd iscipl inary ecocritical approaches successfully enlighten the engagement of U IsterScots poetry, as a unique from of cultural expression, with the natural world. This thesis provides a study of poetry from six of the foremost Ulster-Scots poets of the Romantic and early Victorian eras. A range of poems that engage with nature and environment are analysed in this thesis using applicable methodologies from ecocriticism. The primary aim of this thesis is to examine the relationship between Ulster-Scots poetry and nature, in the late eighteenth and early nineteenth century. Representations of human ecology, natural phenomena and the physical environment are analysed in the poems studied in this thesis, in particular to establish how they are mediated by literary, linguistic and cultural traditions. This thesis reveals that Scottish and eighteenth-century neoclassical genres form a major basis for the Ulster-Scots poetic engagement with nature and the environment, ofthis era. The pastoral genre is also particularly prevalent in Ulster-Scots poetry and reflects both a literary-cultural preference, and the rural, agricultural habitat that is a genuine everyday experience for many of these poets in Ulster. As a consequence the complex social and environmental impact of agricultural improvement, in the latter half of the eighteenth century, and the advance of urbanisation and industrialisation in the nineteenth century, in the north of ireland; are major themes in Ulster-Scots poetry of this era.