The Museums Act 1845 had given British boroughs the power to levy a small rate for the support of public museums and libraries. Sunderland was the very first municipality to act on it outside London. In 1846 the new museum opened in the Athenaeum Building on Fawcett Street, a converted Georgian structure that had begun life as a literary society. Four years later, in 1850, Sunderland Corporation commissioned an oil painting of the opening of the new South Dock - the first time, as far as anyone has been able to verify, that a British town council had commissioned a work of fine art. By the 1870s the collection had outgrown the Athenaeum. A new building was approved, on a site abutting Mowbray Park, with a Winter Garden in iron and glass modelled on Joseph Paxton's Crystal Palace. Grant's foundation stone was laid in 1877. The doors opened in 1879.

The collection is deliberately broad - this was a Victorian municipal museum and it was intended to educate the working population of a coal port in everything natural philosophy and the arts could teach. Among the highlights: the only known British example of a gliding reptile, the oldest known vertebrate capable of gliding flight, found in Eppleton quarry near Hetton-le-Hole. A stuffed lion acquired in 1879 when the building was new. The remains of a walrus brought back from Siberia in the 1880s, in the era when British whalers and traders still ranged the high Arctic. The first Nissan car manufactured in Sunderland - the Nissan plant at Washington opened in 1986 and transformed the local economy after the colliery closures, and the museum keeps that first car as a piece of late-20th-century history. There is also Sunderland Lustreware, the locally made copper-glazed pottery that flourished in Wearside in the 19th century, in one of the largest collections in the country.

In 1913, John Alfred Charlton Deas, a curator at Sunderland Museum, did something unusual for his profession. He invited the local Council Blind School to visit the museum and physically handle items from the collection. The school accepted eagerly. A photograph survives showing a blind teacher - himself sightless - guiding a blind child's hands over the shape of a First World War helmet. The handling sessions continued and expanded; Deas pioneered a way of museum access that takes decades to spread to other institutions. The image, captioned 'My Daddy Wears one of These,' became one of the museum's defining artefacts in its own right - a record of an early act of inclusion in a public institution that, like many such acts, has never been fully celebrated outside the place that did it.

The Winter Garden was destroyed by a German parachute mine in 1941. A 1960s replacement extension took its place but lacked the original's character. In 2001 a major Heritage Lottery refurbishment built a new Winter Garden alongside the museum - more than 2,000 flowers and plants under glass once again, restored to something close to the Victorian original's ambition. In 2003 the museum was recorded as the most-attended outside London. The Lowry connection arrived gradually. L S Lowry, the great Manchester painter of industrial Lancashire, discovered Sunderland in 1960. 'One day I was travelling south from Tyneside,' he wrote, 'and I realised this was what I had always been looking for.' He made Sunderland his second home and painted Wearside for the rest of his life. Today Sunderland Museum holds six of his works directly and another thirty on long-term loan - a Lowry collection exceeded only by Salford and Manchester themselves. The dinosaur bone in the cabinet was found in someone's Sunderland garden in 2011. The pretext for opening the museum in 1846 was that the working people of a coal port deserved access to art and science. It is still being honoured.