Porträt des William Brabazon Ponsonbony, 1st Baron Ponsonby, of Imokilly

William Brabazon Ponsonby, 1st Baron Ponsonby, painted by Lawrence around 1800 in a portrait not definitively attributed to a named institution, was a senior Whig politician whose career in the age of Pitt and Fox embodied the patrician reform tradition. The Ponsonby family had been among the most prominent in Irish Whig politics for generations — his father William had been Speaker of the Irish House of Commons — and Lord Ponsonby's career in the Westminster Parliament continued this tradition of liberal aristocratic politics. He served as lord-in-waiting, held various court appointments, and was eventually created Baron Ponsonby in 1806 as a mark of Whig favor. Lawrence's Whig portraits form a coherent sub-category of his practice that collectively documented the opposition political culture of the Regency era; figures like Ponsonby, Fox, and Grey — painted with the same technical mastery Lawrence brought to their Tory opponents — demonstrate his professional neutrality in the political divisions that were shaping the era. The portrait's current location uncertainty reflects the complex provenance of smaller-scale Lawrence works that passed through the art market without entering major museum collections.

Lawrence conveys diplomatic polish and intelligence through careful handling of the face, with alert eyes and a composed expression befitting a man trained in the subtleties of international negotiation. The warm flesh tones and confident brushwork are characteristic of Lawrence's work around 1800.