[1] The title De expugnatione Scalabis ('On the Conquest of Santarém') was given to the text by Alexandre Herculano in his 1856 edition for the Portugaliae Monumenta Historica.
[2] The text is preserved in one manuscript, now Lisbon, Biblioteca Nacional de Portugal, Fundo Alcobacense 415, which was copied at the Cistercian monastery of Alcobaça in the late twelfth[3] or mid-thirteenth century.
[3] Its incipit is an invitation to Christian worship—Cantemus domino fratres karissimi ('Let us sing to the Lord most dear brothers')—that parallels the invitatory Psalm 95.
[9] Wilson argues that Goswin of Bossut may be the author of the Scalabis, having been commissioned by Bishop Soeiro Viegas around 1217–1225 to rework a preexisting liturgical office celebrating the conquest of Santarém.
Soeiro is known to have commissioned from Goswin the De expugnatione Salaciae carmen, a song celebrating the siege of Alcácer do Sal in 1217.