A state becomes a “commonwealth” in name rather than in legal status; the distinction is mostly historical and stylistic, not constitutional or legal. Key points

• The term is ceremonial: in the United States, the four states that use it—Kentucky, Massachusetts, Pennsylvania, and Virginia—are legally states just like any others. The word commonwealth carries no special legal privileges or differences in governance. This is the core idea shared by most authorities today.

• Historical and philosophical origins: “commonwealth” originated in English political usage to denote a polity founded for the common good, drawing on ideas from Latin res publica and early modern thinkers. This reflects the intent behind adopting the term in those state constitutions.

• Practical effect: in practice, there is no difference in how laws apply, how elections are conducted, or how the federal government interacts with these four states compared with others. The label is largely symbolic and historical.

• Other uses of the term: outside the four states, “commonwealth” can appear in other contexts (territories or interchangeable usage with “state” in certain constitutional phrases), but again it does not create a separate legal status.

Concise takeaway

• Being a “commonwealth” is a historical/nominal designation with no separate legal status or governance implications in the U.S.; the four states that use it simply chose that terminology in their constitutions to emphasize government for the common good.