Commonplace among C15th humanists to refer to Turks as 'Teucri' (Trojans). Bracciolini, Ficino, Bruni all used it, even Pope Eugene IV. Then post-1453 term became politicised. Active campaign began against use of 'teucri'.
Wrote Cardinal Aeneas Piccolomini (the future Pius II) to Pope Nicholas V in 1453.