Neckdeep

This gave me a hint, and I went knee-deep, and sometimes neck-deep, in the Red Weed. The density of the weed gave me a reassuring sense of hiding.

By the start of the 19th century, Europe was neckdeep in the Napoleonic Wars, which, at various times, amounted to the British Empire against Europe, and, at others, involved Britain subsidising various nations, such as Austria and Prussia, against Napoleon.