The City of Birmingham Symphony Orchestra (CBSO) has appointed Mirga Grazinyte-Tyla as its musical director.
The 29-year-old, who is currently assistant conductor at the Los Angeles Philharmonic, will be the only woman to lead a UK orchestra.
Her appointment makes London's orchestras look "stale and middle-aged," said critic Norman Lebrecht.
Replacing Andris Nelsons, Grazinyte-Tyla becomes the CBSO's chief conductor with effect from September 2016.
The Lithuanian musician made her debut with the orchestra in July 2015 and impressed the players so much that she was invited back last month to conduct a specially-arranged concert featuring works by Debussy, Schumann and Sibelius.
Reviewing the performance, The Guardian wrote: "She communicated something wonderfully alive and detailed to the players... [This was] a performance with fresh, clear textures and an unswerving sense of shape."
Grazinyte-Tyla told BBC Radio 3's In Tune she was offered the job shortly afterwards.
Announcing her appointment, the orchestra's chief executive, Stephen Maddock, said Grazinyte-Tyla had established "an instant chemistry" with the orchestra.
"Mirga is 29 and is thrilling audiences wherever she goes," he added. "We can't wait to start making music with her."
The conductor, a protege of Gustavo Dudamel, told the BBC: "I had the feeling, with the CBSO, it didn't matter which direction you would look, they are open to every impulse. It is a huge gift for a conductor.
"I believe we will be a great team and really look forward to making music together."
The CBSO is known for its spotting and promoting young talent. Its previous music directors include Sir Simon Rattle, who was appointed at just 25 years old, and Sakari Oramo, who is now with the BBC Symphony Orchestra.
Grazinyte-Tyla's immediate predecessor, Andris Nelsons, now leads the Boston Symphony Orchestra.
"My time with the orchestra will always be very special to me and I am sure Mirga will also be inspired by the wonderful musical family of the CBSO," he said.
Nelsons left prematurely in summer 2015, and recent months have seen several potential replacements perform with the orchestra in concerts that doubled as thinly-veiled auditions.
'Force of nature'
The daughter of two musicians, Grazinyte-Tyla went to school in Vilnius, Lithuania, and studied voice.
"As a teenager, I thought singing might be an interesting option," she told the LA Times last year. "Then, in the last years at school, we started to work with a choir and orchestra. I was loving it - being with the music and people at the same time."
She pursued her studies in Zurich, Leipzig and Bologna, eventually graduating with a bachelor's degree in choral and orchestral conducting from the University of Music and Fine Arts, Graz, Austria.
In 2012, she won Salzburg's young conductor competition in 2012; and was last year appointed musical director of the Salzburg Landestheater.
Among her conducting credits to date are appearances with the Gustav Mahler Youth Orchestra, the Beethoven Orchestra Bonn, the Danish National Symphony Orchestra, Berlin's Komische Oper and the Kremerata Baltica.
The LA Times described her as "a natural leader and a musical force of nature" after her 2014 debut with the LA Philharmonic at the Hollywood Bowl.
"Her conducting style is striking. Standing erectly with her legs apart and stationary, she operates from her upper body, vivaciously waving her arms as though corralling the musicians," wrote Mark Swed.
"My guess is that before long she will be known simply as 'Mirga'."
Full details of the musician's opening season with the CBSO will be announced in April.
Although she will be the UK's only female music director, she will not be the first. Marin Alsop previously held the post at the Bournemouth Symphony Orchestra, as did JoAnn Falletta with the Ulster Orchestra.