Grosse was born as the son of a chemical laboratory technician and a geologist in the city of Stralsund in Mecklenburg-Vorpommern (then East Germany) and grew up with an older brother in Stendal.
After he became Minister of State for Science and Art in 2002, Grosse took over the position of Head of Department for Press and Public Relations in the ministry.
In 2007, Grosse took over the position of press spokesman in the Saxon Ministry of the Interior under Albrecht Buttolo [de], before being called to the State Chancellery as head of the public relations department a year later, where he worked for the then Minister-President Stanislaw Tillich.
In 1994, Grosse joined the Christian Democratic Union of Germany (CDU) and was particularly active in the Dresden district association.
As a result of an internal debate about the COVID-19 pandemic in Germany, a falling out with the federal chairman of the Free Voters and Bavarian Minister of Economic Affairs Hubert Aiwanger arose in 2020 after Grosse had written a letter to Minister-President of Saxony Michael Kretschmer in April calling on him to lift the lockdown restrictions.
[5] In February 2021, Grosse founded the Citizens' Alliance Germany in Rodewisch, which set itself up as a federal party with a regional association in Saxony.
[6] In March 2021, Grosse also joined the Bürgerlich-Freiheitlicher Aufbruch, which, as a registered association, formed a collective movement of liberal-conservative forces from various parties.
[8] On 20 November 2022, just a few days after ending his membership in the Citizens' Alliance, he was a founding member of Bündnis Deutschland in Fulda and was elected federal chairman of the new party.