Assembled and composed for Leipzig's Christmas season, Bach's Christmas Oratorio is a celebration of the nativity of Jesus Christ originally performed over the course of six days beginning on Christmas Day As was often Bach's practice, he re-used music from several earlier works, including the independent secular cantatas nos. In addition to chorus, the work features soprano, mezzo-soprano, tenor, and baritone soloists, as well as an orchestra configured differently for each of the six sections. For these performances, Andris Nelsons and the orchestra are joined by an outstanding group of soloists and the Tanglewood Festival Chorus. In November , he and the orchestra toured Japan together for the first time. In February , he became Gewandhauskapellmeister of the Gewandhausorchester Leipzig, in which capacity he brings both orchestras together for a unique multi-dimensional alliance.