The norms and expectations for photographic portraits changed enormously between World War I and World War II.
Whereas studio portraits of the early 20th century usually featured stolid postures and grave expressions, these customary styles were abandoned by the 1920’s.
One assumes that this change was fueled by the general relaxation of stern habits in the 20’s, the birth of a distinct “youth culture” as population swelled, and (perhaps, most importantly) by the replacement of studios by personal cameras and amateur photographers.
https://www.befunky.com/learn/a-history-of-portrait-photography
This snapshot, not a postcard, suggests another possible reason – the influence of movie studios and fan magazines.
The iconography of the “star” photo shoot seems to be imitated by this young man lolling on the grass.
The full body pose, the camera gaze, the sultry expression – looks like a publicity shoot.
Here is a summary from Google:
“Movie magazines, with their focus on celebrity portraits and cinematic aesthetics, have significantly influenced portrait photography, leading to the adoption of cinematic styles, a focus on visual storytelling, and a heightened awareness of lighting and composition…”
The photograph is not dated, but this image was attached to another photograph of the same young man wearing a navy uniform of the Second World War.
I am assuming that this snapshot was made in the 1940’s, but I cannot prove that this is so – I am not an expert in military attire.
One hopes that our hero found many others to appreciate his photogenic charms.
