Paul Costelloe Dies at 80, Architect of Princess Diana's Wardrobe

Paul Costelloe, the Irish fashion designer who served as a personal designer to Princess Diana and became a fixture at London Fashion Week for four decades, died on November 22 in London at the age of 80, his family said. He passed away peacefully surrounded by his wife and seven children following a short illness, according to the family statement issued on Saturday.

Costelloe was appointed as Diana's personal designer in 1983 and their collaboration continued until her death in 1997. That partnership positioned him at the intersection of celebrity influence and design credibility at a moment when royal patronage still had rare power to shape public taste and global demand. He trained in Dublin and honed his craft with early work in Paris and Milan before establishing his own label, ultimately leading all his collections from a studio in central London.

His career paralleled the rise of London as a fashion capital. Invited to show at London Fashion Week in its inaugural year in 1984, Costelloe was one of the designers whose steady presence helped the event evolve from a British showcase into a platform with international relevance. Over four decades he maintained visibility and relevance at a time when the industry moved from traditional couture cycles to a media saturated, celebrity driven marketplace.

The business implications of his career are notable. Costelloe built a label that leveraged high profile endorsement into a durable commercial enterprise, exemplifying how designers can translate prestige dressing into a brand with broader retail legs. His long running role in London Fashion Week also illustrated the value of continuity and heritage in a sector increasingly focused on novelty and rapid turnover. For the British fashion industry, his career underlined the commercial benefits of linking design credibility to celebrity and institutional platforms.

Culturally his influence was amplified by association with Diana, whose wardrobe remains a subject of study for its mix of accessibility and symbolism. Designers who dressed the princess contributed to a visual language that resonated across class and national boundaries. Costelloe’s body of work spoke to an era in which public figures functioned as curators of style and taste for global audiences, and his death invites reflection on that dynamic as the fashion world recalibrates around new forms of influence.

Irish political and cultural figures noted his significance. Ireland's Deputy Prime Minister Simon Harris called him "remarkable" and hailed his career as "a quite remarkable Irish success story." Costelloe’s trajectory from Dublin training rooms to the runways of London, Paris and Milan underscored the transnational pathways available to Irish creatives in the late twentieth century.

As the fashion industry confronts questions of sustainability, speed and legacy, Costelloe’s career will be examined as an example of how steady craft, strategic collaboration and brand building can sustain a designer across changing tastes. His death closes a chapter in late twentieth century fashion, and revives attention on the ties between celebrity, commerce and cultural memory.