The author of this poem is Bernard Barton “The Quaker Poet” who spent most of his life as bank clerk in Woodbridge, Suffolk.
Dunwich in Suffolk was, in early medieval times, the sixth largest city in England, a major international port, and shipbuilding centre. The town had nine churches and two monastic sites. But in 1286, storms destroyed the harbour, and silting blocked the river. The town gradually decayed, and was swallowed by coastal erosion. It had already largely vanished in the mid 19th century when Barton wrote, and All Saints Church (pictured below in 1900) fell into the sea in the early 20th century. More details of the history can be found here.

Dunwich
In Britain's earlier annals thou wert set Among the cities of our sea-girt isle: Of what thou wert - some tokens linger yet In yonder ruins; and this roofless pile, Whose walls are worshipless, whose tower - a mark, Left but to guide the seaman's wandering bark!
Yet where those ruins grey are scatter'd round, The din of commerce fill'd the echoing air; From these now crumbling walls arose the sound Of hallow'd music, and the voice of prayer; And this was unto some, whose names have ceased, The wall'd and gated City of the East!
Thus time, and circumstance, and change, betray The transient tenure of the worldly wise! Thus "Trade's proud empire hastes to swift decay," And leaves no splendid wreck for fame to prize. While nature her magnificence retains, And from the contrast added glory gains.
Still in the billowy boundlessness ouspread, Yon mighty deep smiles to the orb of day, Whose brightness o'er this shatter'd pile is shed In quiet beauty. - Nature's ancient sway Is audible in winds that whisper round, The soaring sky-lark's song, the breaker's hollow sound.
Bernard Barton (1784-1849)
