Among a sea of men in black tailcoats, there was one guest, dressed in a light silk kimono, who easily stood out during the rituals-steeped accession ceremony for Japan’s new emperor: Satsuki Katayama. As the only female minister in the current government’s cabinet, Katayama, 59, earned herself a place in the history books today as she became the first woman in modern times to officially witness the ceremony. The Regalia Inheritance ceremony, which took place at 10.30am this morning inside the Imperial Palace in Tokyo, is traditionally off limits to all female members of the Imperial family, with neither the incoming nor outgoing empresses attending. Katayama, 59, was the only woman among a small exclusive group of otherwise all-male guests, including representatives of three branches of government and adult male royals in line to the throne who witnessed the historic event, the first stage of Emperor Naruhito’s accession to the throne. During the ceremony, the Imperial chamberlains entered the room and placed the state and privy seals, along with cases containing a sword and a jewel, two of Japan’s Three Sacred Treasures, on cypress wood stands in front of Emperor Naruhito as proof of his rightful succession. Japan's new Emperor Naruhito receives the Imperial regalia of sword and jewel as proof of succession at the ceremony at Imperial Palace in Tokyo Credit: AP Later in the morning, female members of the Imperial family and the female spouses of government officials – including the kimono-clad wife of prime minister Shinzo Abe – were able to enter the same state room, before the new emperor made his inaugural address to the nation in his new role. While the nation’s mood was widely optimistic as a new era dawned, the absence of female royalty at the ceremony cast a critical spotlight on the role of women in Japan’s Imperial family and its traditionally archaic rules. A vehicle carrying Japans Empress Masako arrives at the Imperial Palace in Tokyo Credit: TOSHIFUMI KITAMURA/AFP Among the most well known is its controversial male-only succession law, which prevents women from coming to power, while female members must also officially leave the royal family upon marriage. The ceremony’s VIP guestlist also highlighted the dire scarcity of women reaching the upper echelons of the political world in Japan, despite the government’s highly publicised push for policies of so-called “womenomics” to improve the nation’s poor track record in gender equality. Satsuki Katayama Credit: ERIKO SUGITA/Reuters Katayama, 59, is a high-flying anomaly in a male dominated world of politics. A law graduate from prestigious University of Tokyo, she is currently minister of state for both regional revitalisation and gender equality – and the only woman among 19 men at the highest cabinet level of the ruling Liberal Democratic Party of Japan. Following a successful career as a bureaucrat at the Ministry of Finance, she was first elected to the House of Representatives in 2005, and served as a deputy minister of economy, trade and industry, before losing her seat four years later. She was reelected three years ago, with her profile swiftly rising in Mr Abe’s current government. One of dozens of so-called “Koizuimi Children”, the launch of her political career was initially championed by popular reformist former prime minister Junichiro Koizumi, who hailed her as “a madonna of reform”.