Final answer:
Fitzgerald portrayed the 1920s as a period of personal literary success mixed with unfulfilled dreams and disillusionment, a theme echoed in 'The Great Gatsby' reflecting the era's pursuit of dreams amidst societal decay.
Step-by-step explanation:
F. Scott Fitzgerald's life in the 1920s was characterized by literary success but also personal challenges. He describes this period as one filled with a mix of regret and independence, where he grapples with unrealized athletic and military aspirations, yet finds solace in his work and so-called imaginative heroism. His depiction not only offers an intimate look at his personal struggles but also reflects the broader theme of the 1920s as a time of disillusionment, the pursuit of independence, and the sometimes hollow allure of success—a theme also present in his masterpiece, The Great Gatsby. The nostalgia and pursuit of dreams amidst societal decay in the novel echo Fitzgerald's own experiences and perceptions of the decade as interesting yet fundamentally unsatisfying.