Why did Dreyfus immediately come under suspicion in the spying case?

Alfred Dreyfus came under suspicion in the spying case primarily due to his Jewish background, which fueled anti-Semitic sentiments in France at the time. Additionally, he was an officer in the French Army and was falsely accused of passing military secrets to Germany, leading to his quick scapegoating amidst rising national tensions. The lack of concrete evidence against him, combined with a biased military tribunal, further contributed to the immediate suspicion and his subsequent conviction.