Short answers, pulled from the story.
Historical Lombardy, also called Greater Lombardy or Granda Lombardia, refers to a territory larger than the modern Italian administrative region around Milan. At its broadest, it was synonymous with Northern Italy as a whole, bound together by shared cultural, linguistic, and political identity.
In De vulgari eloquentia, Dante Alighieri recognized Romagna and Genoa as autonomous from Lombardy. This was one of the earliest formal acknowledgments that the broader Lombard concept had defined cultural and geographic edges.
From the 1400s, Piedmont began moving toward its own cultural identity, separating from the broader Lombard world. By the 1600s, a substantial partition existed between Lombardy and Piedmont, with Piedmont governed by the House of Savoy.
Massa Lombarda in Romagna and Reggio di Lombardia in Emilia are two towns that preserved the old Lombard label in their names. Reggio di Lombardia was later renamed Reggio nell'Emilia after the unification of Italy.
Reggio di Lombardia was renamed Reggio nell'Emilia after the unification of Italy, dropping its Lombard label in favor of its regional identity in Emilia. The city kept the old Lombard name in its official title until that point.
Historical Lombardy originally covered Northern Italy broadly. Dante Alighieri's De vulgari eloquentia marked an early recognition that Romagna and Genoa lay outside it. By the 1600s, Piedmont had separated under the House of Savoy, leaving Lombardy with a substantially reduced extent.