В пьесах начала 17 века The Gentleman Usher и The Wisdom of Doctor Dodypoll присутствует сюжет о том, как правитель отец и принц сын любят одну и ту же женщину, и отсюда возникает конфликт. Фаворит герцога Альфонсо некий Медиче (на самом деле цыганский предводитель Мендиче, т.е. "нищий") - возможно отражение таких фаворитов "Грозного", как медик Е.Бомелей, прибывший на Русь кстати из Англии, также Михаила Глинского, мистра Леона Иудея, Схарии, библейского Мардохея? Во второй пьесе герцогиня, которую герцог (также Альфонсо) хочет оставить ради Hyanthe - возможно отражение законной жены Грозного (Софьи Палеолог). Ранение на охоте в первой пьесе - не то же ли, что и убийство Тлеполема у Апулея? Маргарита (Есфирь?) первой пьесы обезображивает свое лицо, этот же мотив есть в The Trial by Chivalry, где отверженный жених плескает в лицо героини яд, в результате она становится похожей на прокаженную (в обоих случаях доктор вылечивает героиню) - не то же ли это, что и страдания Зулейхи (Юсуф и Зулейха) или Крессиды ("Завещание Крессиды")? Во второй пьесе отмечено некоторое сходство со "Сном в летнюю ночь" Шекспира.

http://en.wikipedia.org/wiki/The_Gentleman_Usher

Об источниках пьесы:
https://archive.org/stream/allfoolesandgen00chapgoog#page/n200/mode/2up
Sources. The immediate source of the play is not known. The love-intrigue is so clearly conceived and so steadily carried through as to suggest that Chapman, whose forte was by no means invention, borrowed it entire from some French or Italian novel. A few scenes to which attention is called in the Notes are suggested by, or perhaps borrowed from, the earlier play of Sir Gyles Goose-cappe. As to the connection between the characters of Bassiolo and Malvolio see Introduction, pp. xliii, xliv.
..Professor Koeppel has pointed out certain similarities between The Gentleman Usher, on the one hand, and the anonymous plays, The Wisdom of Dr. Dodypoll, and The History of the Trial of Chivalry, on the other. The first, printed in 1600 and reprinted by Mr. Bullen (Old Plays, vol. III, 1884), tells among other things the story of the unsuccessful passion of a Duke Alphonso for the Lady Hyanthe, daughter of Earl Cassimere, who loves and is beloved by the Duke's son, Alberdure. Apart from the name of the father, Alphonsus, the only thing in common to the plays is the theme of the father's love for his son's mistress, and this may go back in each case to a common source, the story of Zenothemes and Menecrates in Lucian's Toxaris.
The similarity between two episodes in The Gentleman Usher and The Trial by Chivalry is more apparent. In the latter play, entered S. R., December 4, 1604, but probably written much earlier, the metre and technic point to the sixteenth century. A rejected suitor smears a lady's face with poison which makes her "spotted, disfigured, a loathsome leper." The prince to whom she is betrothed, however, insists upon carrying out his contract of marriage, although the lady declares that she is unworthy. The situation is closely akin to that in the last scene of The Gentleman Usher, and the similarity heightened by the fact that in each case the lady is cured by a wonder-working physician, in The Gentleman Usher by Benivemus, in The Trial by a hermit, skilled in "physic." It seems quite possible that Chapman lifted the whole episode of the poison from this earlier play.

http://www.enotes.com/topics/gentleman-usher The Gentleman Usher Summary - неполностью, требуют регистрации

http://en.wikipedia.org/wiki/The_Wisdom_of_Doctor_Dodypoll

О пьесе The trial of chivalry пока ничего не нашел, кроме самого текста на англ. яз в старой редакции:
https://archive.org/details/cu31924013325422 The trial of chivalry. 1605 (1912)