The papers of Francis Walsingham, being the first batch of secretarial documents deposited in the State Paper Office, initiated the whole business of archiving English State Papers and illustrated how the early State Papers were dispersed into private collections. This article aims to present the formation of the Tudor State Papers by explaining Walsingham’s secretarial procedures in registering, deciphering, summarizing, duplicating, categorizing, and depositing documents. More significantly, the dispersing routes of Walsingham’s papers after his death in 1590 will be reconstructed by tracing backwards from their present distribution. This fragmentation arose chiefly from four causes: retention by Walsingham’s servants either for their immediate keeping or for new patronage; the “public-only” selection policy; theft by Jacobean antiquarians; and various transfers via loan, marriage, sale, inheritance, or bestowal. The formation and dispersal of Tudor State Papers reveals the “invasion” of Elizabethan espionage network, state information system, and government administration by ministerial clienteles.