Is it important to read the entire "Dwellers" series prior to beginning the "Country Saga" or can they be read simultaneously?
Great question, Katy! The first three Dwellers Saga books (The Moon Dwellers, The Star Dwellers, The Sun Dwellers) are completely separate from the three Country Saga books (Fire Country, Ice Country, Water & Storm Country). That means you can read either series first, or even skip back and forth, whichever you prefer ;)
However, BEFORE reading the 7th and final book (The Earth Dwellers) in the combined series, you'll want to have read the first six books in their entirety as the last book combines characters and plotlines from both series into an epic finish!!