This flag was used by Rosbercon Girls Grammar School, which operated in Brighton from 1906 until 1941.
The school was established in 1906 by the Tisdall family. The Tisdalls were a family of educators: Irish-born Henry Thomas Normanton Tisdall and his wife Lucy taught for many years at the Walhalla State School in Gippsland, along with Lucy's sisters Alice and Clara Weekes. Three of the Tisdall daughters, Ethel, Constance and Theodosia (Theo) followed their mother and aunts into the teaching profession. Constance in particular considered education her true calling and harboured a dream of one day being principal of her own school.
After Henry's death in 1905, faced with financial uncertainty and several unmarried daughters to support, Lucy Tisdall decided to take a risk. She sold the family's Toorak home and, together with her sister Alice, leased 'Ashburnham', a large Victorian villa at 106 North Road, Brighton. The plan was to open a private school, with Ethel and Constance as co-principals and Lucy, Alice and Theo teaching and managing the household affairs. This came as a "joyful surprise" to Constance, who was only informed of the plan after it had been finalised.
The school was named Rosbercon after Henry's home village in County Wexford, Ireland. The crest, designed by son Bert Tisdall around 1910, featured a crowned letter 'A' above the motto "amor vincit omnia" ("love conquers all"), both inspired by a verse in Geoffrey Chaucer's "The Prioress's Tale": "about her arm she bore/A paire of bedes gauded all in grene,/And theron heng a broche of gold full shene,/On which there was first writ a crowned 'A',/And after, Amor Vincit Omnia." It was a motto Constance held close to her heart, embodying her values as a teacher. Reflecting in 1961, she wrote, "In a school without punishments, a school with love and understanding between teacher and pupil - with a love of teaching on one side, and a desire to learn on the other, love would indeed conquer all."
The school's opening day in 1906 proved less than auspicious, with no pupils arriving at all. The women persisted and by the end of the first week, five students had been enrolled. From here, the school grew steadily in size. A new schoolroom designed by architect Harold Desbrowe-Annear was built in the house's orchard to accommodate the increasing numbers, but by 1911 the Tisdalls began looking for larger premises. They leased the nearby property 'Hazeldean' at 124 North Road and, during the 1912 school holidays, the Desbrowe-Annear schoolroom was raised onto a lorry drawn by sixteen horses and moved down the road to what would become Rosbercon's new home.
In 1923, Constance instituted a modified version of the Dalton Plan, an education model based on individualised learning. Girls in senior years were encouraged to work more independently, making regular use of the reference library and working to a monthly assignment schedule. The school performed well academically and in competitive sport, but over time was eclipsed by the nearby Firbank Church of England Girls' Grammar School (established 1909), whose institutional backing provided it with access to wider resources and facilities than those of the small family-run Rosbercon.
At the end of 1933, Ethel and Theo retired and Constance became principal of St Anne's Church of England Girls' Grammar School (now Gippsland Grammar) in Sale. Rosbercon was sold to Miss Iris Hay, who served as principal from 1934 until the school's closure in 1941.
Following her own retirement in 1947, Constance Tisdall settled in Erica Avenue, East Malvern, in a house named 'Rosbercon' after her former school. She continued teaching English literature, mostly to migrants, and enjoyed regular visits from former students. Well into the late 1960s, old Rosbercon girls continued a tradition of coming together for an annual reunion on the first Saturday in November, on which day Constance would fly the school flag at her home.
Large navy blue flag with horizontal maroon stripe at top and bottom, and school crest in centre. Stylised maroon "A" topped with yellow crown. Yellow scroll below with motto in navy blue letters: "AMOR.VINCIT.OMNIA".