SEOUL, South Korea — Her mother was shot by an assassin. Her father, a staunchly anti-Communist dictator, was similarly killed. And she survived a vicious razor attack to the face.

Nobody doubts the toughness of South Korea’s new president, Park Geun-hye, whose upbringing has made her as steely a leader as they come. Now at the center of an escalating crisis with North Korea, Ms. Park, 61, is her country’s first-ever female leader, a fact that her rivals in the North have raised to taunt her.

Stories of her mental toughness are legend — on learning that her father had died, her first concern was whether North Korea was preparing to invade. Her first question after awakening from an operation after the razor attack in 2006, which left a scar across her jaw, was how her party’s campaign was going.

Ms. Park is so tough-minded that even in South Korea, still one of Asia’s most patriarchal societies, her gender has mainly been a nonissue after some initial jitters.