Dagome iudex is one of the earliest historical documents relating to Poland. Poland is not mentioned by name, but reference is made to Dagome and Ote (Mieszko I and his wife, Oda von Haldensleben) and their sons in 991, placing their land (called "Schinesghe") under the protection of the Apostolic See. The document's name derives from its opening words.
The Dagome iudex survives only in the form of a summary, completed c. 1080. It was found in a register compiled by a curial cardinal during the papacy of Gregory VII.
Most historians believe that the word "Dagome" is a melding of two names: the Christian "Dago," for "Dagobert" (Mieszko's hypothetical baptismal name), and the Slavic "Me," for "Mieszko." The Latin word "iudex" ("judge") would be used in the meaning of "prince." Another interpretation is that "Dagome iudex" is a corruption of "Ego Mesco dux" ("I, Prince Mieszko"). In the Vatican copy the e of Dagome might have an s adscriptum (similar to cedilla), though just the Vatican copyist read iudex literally, relating it to Sardinia and its four "judges".
Place names are misspelled by the person who made the summary. He was also apparently unaware that the document related to territory later called Poland.
The boundaries of the "Gniezno" state are described as extending to the "Long Sea" (the Baltic), Prussia, Rus', Kraków, Moravia and the Oder River. Lesser Poland is taken account by the mention of its capital, Kraków ("craccoa"). Between alemura, probably Olomouc, and Upper Lusatia region of the Milceni (terra mileze) the border could include Silesia if it was straight.