Book I: Miss Brooke
Mentioned as a learned but dry clergyman and scholar whom Dorothea admires from afar, seeing him as a model of intellectual and spiritual greatness.
Chapter I
A learned clergyman expected to dine at the Grange; Dorothea holds him in high veneration and sees him as a potential mentor.
Chapter II
Speaks at length about his scholarly work and need for a reader; Dorothea finds him deeply interesting and compares him to Locke.
III
Visits Tipton and engages Dorothea in lengthy conversations about his scholarly work on mythical systems. He speaks to her as a fellow student, using Latin and Greek phrases, and shows indifference to her interest in building cottages.
IV
Mentioned as the object of Dorothea's admiration; his pamphlets and proposal offer are central to the chapter.
V
His letter proposing marriage is read and accepted; he later shares a joyful tête-à-tête with Dorothea, delighted by her ardor.
Chapter VII
Agrees to teach Dorothea, but views her studies as a way to save his eyes and as a prelude to marriage, which he anticipates as a source of female tendance.
VIII
Discussed by Sir James and the Cadwalladers; defended by the Rector as a scholarly and just man, though criticized for his lack of passion and social awkwardness.
Chapter IX
Shows Dorothea around Lowick Manor, introduces her to Will Ladislaw, and demonstrates formal courtesy.
Chapter X
Anxious to inspect Vatican manuscripts; experiences a 'blankness of sensibility' and loneliness despite his marriage; leans on Dorothea's veneration for encouragement in his authorship.
XI
Casaubon is mentioned as a contrast to Lydgate: a wealthy, learned man who married Dorothea to adorn his life, while Lydgate is young and ambitious.
Book II: Old and Young
Casaubon's scholarly obsessions and emotional distance become more apparent, contributing to Dorothea's unhappiness.
XIX
Mentioned as Dorothea's husband and Will's second cousin; not present in the scene.
Chapter XX
Remains emotionally distant and absorbed in his studies at the Vatican; makes a stilted, formal speech to Dorothea about Rome and marriage, revealing his lack of empathy.
XXI
Mr. Casaubon is absent during the visit, busy reading at the Vatican Library. He is discussed as a benefactor and scholar, but Will's remarks cast doubt on the value of his work, and he enters the room at the end of the chapter.
Chapter XXII
Referenced throughout as the subject of debate; his scholarly work and generosity are discussed, though he is not present.
Chapter XXVIII
Returns to Lowick Manor, complains of palpitation, and is in the library giving audience to his curate Mr. Tucker.
XXIX
Revealed as spiritually hungry and self-conscious; he married for companionship and a helpmate, but his sensitivity and egoism cause tension with Dorothea.
Chapter 30
Remains offstage but is the subject of the medical discussion; his health is precarious, and he is unaware of the full extent of his danger.
Chapter XXXIV
Coldly polite but irritated by Will's presence; struggles to repress outward signs of displeasure.
Chapter XXXVII
Angrily rejects Dorothea's interference in his affairs, suspects Will of improper motives, and considers how to counter Will's presence in Middlemarch.
XXXIX
Referenced as having forbidden Will from visiting Lowick, and as the subject of Dorothea's hopelessness about influencing his actions.
XLII
Broods over jealousy of Will Ladislaw and Dorothea's perceived judgment; decides to consult Lydgate about his health.
Book V: The Dead Hand
Casaubon's death and the codicil to his will exert a controlling influence from beyond the grave, embodying the 'dead hand' of the past.
XLIII
Referenced as Dorothea's husband; she fears he is concealing a change in his health and has begun a new method of arranging notes.
XLIV
Acquiesces to Dorothea's subscription but feels increasing distrust and loneliness.
XLVI
Referenced indirectly: his prophecy that Will would lose caste is recalled, and town gossip says he has turned the cold shoulder on Ladislaw.
XLVII
Sits opposite Will in church, seemingly aware of his presence; leaves immediately after the service without acknowledging him.
XLVIII
Shows renewed energy in his scholarly work; demands Dorothea's participation in his research; extracts a promise from her to carry out his wishes after his death.
XLIX
Recently deceased; his codicil is criticized as a mean and ungentlemanly action that compromises Dorothea.
Book VI: The Widow and the Wife
Though deceased, Casaubon's influence lingers through his will and the codicil, affecting Dorothea's choices and relationships.
LXXXIII
Referenced indirectly through Dorothea's memory of his prohibition and her study of Asia Minor geography, which he had rebuked her for neglecting.