CESI. - An Umbrian-Sabine family originating from the place of the same name, which began to rise in the 15th century and during the 16th century in one of its branches united the marquisate of Monticelli (1572), the duchy of Acquasparta (1588) and the principality of S. Angelo and S. Paolo (1613). Its fortunes in the Roman Curia began with PAOLO EMILIO, b. in 1481, apostolic protonotary, created cardinal by Leo X in the great promotion of 1 April 1517. With him begins that series of personages who held cardinalships and bishoprics during the 16th century and the beginning of the following one. Indeed Paolo Emilio held Todi in commendam on 1 June 1523; Narni on 20 May 1525, which he transferred to BARTOLOMEO C. a few months later; Orte on 7 April 1525, transferred to POMPONIO C. in 1538; Cervia in 1525, transferred to OTTAVIO C. in 1528, and even Sion in Switzerland, which he held from 12 Nov. 1522 until his death, which overtook him at the age of 56 in the Curia on 5 Aug. 1537. He was also archpriest of S. Maria Maggiore. On the death of Card. Giov. Antonio di S. Giorgio (1511), he acquired his palace in Borgo Vecchio and completed it, converting into a garden the vineyard that extended over the hill behind it and making there an antiquarium of important antiquities taken from the discoveries that were being made everywhere at that time (cf. An. Hülsen, Römische Antikengärten des XVI. Jahrh., Heidelberg 1917; E. Martinori, op. cit. in bibl., p. 47 ff.).
FEDERICO, brother of Paolo Emilio, b. in 1500; he received the bishopric of Todi through his brother's resignation on 11 June 1523 and held it until 1545; he was created cardinal by Paul III on 19 Dec. 1544; he held Cremona in commendam from 18 March 1551 to 13 March 1560; he died as bishop of Porto on 28 Jan. 1565, and was buried at S. Maria Maggiore. He was considered rich, learned and of great experience; he built in Rome the church of S. Caterina dei Funari.
PIER DONATO, was cleric of the Chamber, received the bishopric of Narni in commendam on 25 June 1546 and renounced it in favor of ROMOLO C. on 12 July 1566; he was created cardinal on 7 May 1570 by Pius V. He was legate at Bologna in 1580. D. in the Curia on 29 Sept. 1586 and was buried at S. Maria della Vallicella.
BARTOLOMEO, b. around 1565, held in the Curia the office of treasurer general, which brought him to the cardinalate on 5 Jan. 1596. Archbishop of Conza on 10 March 1608, he renounced it in 1614; on 5 May 1621 he received the see of Tivoli; however he died the same year on 18 Oct. and was buried at S. Maria Maggiore.
Treasurer general was also PIER DONATO the younger, b. around 1583, apostolic protonotary participant on 8 Apr. 1615, then created cardinal by Urban VIII on 16 Dec. 1641, camerlengo of the Sacred College on 9 Jan. 1651, d. in the Curia on 30 Jan. 1656. A contemporary judged: «in the treasurership he was tenacious, free in speech, of vigorous nature, intelligent in business, mediocre in letters» (Cf. Pastor, XIII, p. 716).
Greater fame among posterity was acquired by FEDERICO, b. in Rome on 13 March 1585 to Giovanni Federico, who was the brother of Card. Bartolomeo, and to Olimpia Orsini.
Despite the ill will of his father, who squandered the ample patrimony and in 1622 even alienated to Card. Ludovisi 102 pieces of antiquities from the family collection (Pastor, XIII, p. 50), Federico remained constant in his love for literary and scientific studies and on 18 Aug. 1603, together with Gian Franco Stelluti, Anastasio de Fillia and Giovanni Eckio, founded the Accademia dei Lincei, assuming the name of Coeli-vafus Lyncæus. Only in 1607 was the fifth member added in Giov. Batt. Porta; Galileo Galilei was the sixth and was officially received there on 25 Apr. 1611 on the occasion of his journey to Rome. Galileo himself informs us that «the Lincei are a company of academicians... and have as their aim the study of good letters and in particular of philosophy and other sciences pertaining to it; and moreover the most competent among them attend to writing and publishing their labors» (Edizione Nazionale delle opere di G. Galilei, V, p. 184). C. became a friend of Galileo and remained in contact with him in the following years regarding the discoveries he was making and the controversies they aroused. C. showed particular protection and favor for Galileo on the occasion of his stay in Rome in 1615-16, claiming the freedom of scientific investigation. When it came to publishing a reply to the Libra astronomica of Fr. Grassi, C. together with his colleagues invited Galileo to publish the «Saggiatore» and promoted its printing, which indeed came out under the care of the Lincei themselves in 1623. They had in fact almost to a man embraced Galileo's cause, although C. had only with difficulty been converted to the Copernican system.
At Easter of 1624 Galileo was a guest of C. at Acquasparta. He had moreover made botanical research the field of his studies, in which he may be considered a true precursor.
He had taken special pains for the printing of Galileo's Dialogo dei due massimi sistemi when he died on 1 Aug. 1630, without having had from his two wives Artemisia Colonna (married in 1614) and Isabella Salviati (married in 1616) any surviving male offspring.
The Academy, whose number of members had remained quite limited, entrusted to the care of its protector Card. Barberini, fell silent and soon ceased to exist.