Fausset's Bible Dictionary 
A Canaanite city whose king was one of the 31 subdued by Joshua ( Joshua 13:24). The royal residence of the kings of Israel from Jeroboam to Omri, who removed the capital to Samaria ( 1 Kings 14:17; 1 Kings 15:21; 1 Kings 16:6; 1 Kings 16:17-18); Baasha was buried here. Zimri was besieged here by Omri, and perished in the flames of the palace. Menahem who smote Shallum "went up from Tirzah" ( 2 Kings 15:14; 2 Kings 15:16), but when reigning made Samaria his capital.
Celebrated for beauty ( Song of Solomon 6:4); some derive Tirzah from Ratsah , "pleasant." Its mention is no ground for assigning the Song to a date later than Solomon, as it was in his time the chief city of northern Israel as Jerusalem of southern Israel. The church is "a city set on an hill" ( Matthew 5:14), "well pleasing" to God ( Hebrews 13:21). In the middle ages Brocardus mentions a Thersa on a height three leagues E. of Samaria; this is the exact position of Telluzah, in the mountains N. of Nablus, a large flourishing town, precipitous toward the E. and accessible from the W.; without remains of antiquity; a corruption probably of Tirzah.
Cyclopedia of Biblical, Theological and Ecclesiastical Literature 
The present Teiasir, which Tristram assumes (Bible Places, page 196) as the modern representative, lies twelve miles east by north from Sebustieh (Samaria), and is described in the .Memoirs accompanying the Ordnance Survey (2:228, 245). As to the identity of the name, Lieut. Conder remarks (Tent Work, 2:108):
"It contains the exact letters of the Hebrew word, though the last two radicals are interchanged in position, a kind of change not unusual among the peasantry. The beauty of the position and the richness of the plain on the west, the ancient remains, and the old main road to the place from Shechem, seem to agree well with the idea of its having once been a capital; and if I am right in the suggestion, then the old sepulchres are probably, some of them, those of the early kings of Israel before the royal family began to be buried in Samaria."