The Insatiate Countess is an early Jacobean era stage play, a tragedy first published in 1613. The play is generally attributed to Marston, but some regard Barkstead and Machin as contributors.

Significant and unexplored signs of John Marston's literary rivalry with Ben Jonson are investigated here by Charles Cathcart. The centrepiece of the book is its argument that the anonymous play The Family of Love, sometimes attributed to Thomas Middleton and sometimes to Lording Barry, was in part the work of John Marston, and that it constitutes a whimsical statement of amity with Jonson. The book concerns itself with material rarely or never viewed as part of the "Poets' War" (such as the mutual attempted cuckoldings of The Insatiate Countess and the Middle Temple performance of Twelfth Night) rather than with texts (like Satiromastix and Poetaster) long considered in this light.