Navarre is a region in Northern Spain, but that doesn't really matter. What matters is that this play takes place outside. In Shakespeare's comedies, outside means freedom, fun, and sexual chemistry. (Three of the best things in the world.)
Think cross-dressing in the country in As You Like It, or magical mischief in the forest in A Midsummer Night's Dream. (See "Genre" for more about the influence of pastoral conventions on this play.) We know that the weather is warm enough for the French ladies, denied entrance to the King's Court, to camp on the King's grounds. There's plenty of opportunity for frolicking. Grown men hide in trees, eavesdropping on their friends. The sun, moon, and stars are visible, bewitching everyone and finding their way into love poems.
Outside, in good weather, everyone's feeling frisky.