What was Anna Seward’s earliest known major writing project?

Anna Seward’s earliest known major writing project was a sentimental fictional epistolary journal addressed to an imaginary friend named Emma, which she wrote between 1762 and 1768. This work was published posthumously.1

While Seward later gained significant fame for her poetry—most notably Elegy on Captain Cook (1780) and Monody on Major André (1781)—her early literary efforts primarily consisted of juvenilia, including songs and pastoral poems, before she transitioned to national publishing through her participation in Lady Miller’s Batheaston assemblies.21