Ernst Lindenbauer (18 November 1881 Lichtenegg/Wels – 22 April 1961 Vienna) was Chief Rider from 1919 - 1950 at the Spanish Riding School in Vienna.
The Spanish Riding School (German: "Spanische Hofreitschule" ) of Vienna, Austria, is a traditional riding school for Lipizzan horses, which perform in the Winter Riding School (Winterreitschule) in the Hofburg.
 Not only is it a centre for classical dressage, the headquarters is a tourist attraction in Vienna that offers public performances as well as permitting public viewing of some training sessions.
 The presentation builds on four centuries of experience and tradition in classical dressage.
 The leading horses and riders of the school also periodically tour and perform worldwide.
The airs above the ground or school jumps are a series of higher-level, Haute ecole, classical dressage movements in which the horse leaves the ground.
 They include the capriole, the courbette, the mezair, the croupade and the levade.
 None are typically seen in modern competitive dressage.
 They are performed by horses of various riding academies such as the Spanish Riding School in Vienna and the Cadre Noir in Saumur, and may be seen in other dressage performances.
 The levade and courbette are a particular feature of the Doma Menorquina, the riding tradition of the island of Menorca.
 Horses such as the Andalusian, Lusitano, Lipizzan and Menorquín are the breeds most often trained to perform the airs today, in part due to their powerfully conformed hindquarters, which allow them the strength to perform these difficult movements.
 There were originally seven airs, many of which were used to build into the movements performed today.
Georg Wahl (Kosel, Upper Silesia, 21 February 1920 – 4 November 2013) was Chief Rider at the Spanish Riding School in Vienna, dressage instructor, rider and trainer.
 He was also known as the coach and trainer of Swiss Olympic medalist Christine Stückelberger.
The Lipizzan or Lipizzaner (, Croatian: "Lipicanac" , Hungarian: "Lipicai" , Italian: "Lipizzano" , Slovene: "Lipicanec" ), is a breed of horse closely associated with the Spanish Riding School of Vienna, Austria, where they demonstrate the "haute école" or "high school" movements of classical dressage, including the highly controlled, stylized jumps and other movements known as the "airs above the ground."
 The horses at the Spanish Riding School are trained using traditional methods that date back hundreds of years, based on the principles of classical dressage.
The Piber Federal Stud ("Bundesgestüt Piber") is a stud farm dedicated to the breeding of Lipizzan horses, located at the village of Piber, near the town of Köflach in western Styria, Austria.
 It was founded in 1798, began breeding Lipizzan horses in 1920, and today is the primary breeding farm that produces the stallions used by the Spanish Riding School, where the best stallions of each generation bred at Piber are brought for training and later public performance.
 One of Piber’s major objectives is "to uphold a substantial part of Austria’s cultural heritage and to preserve one of the best and most beautiful horse breeds in its original form."
A riding instructor is a person whose job it is to teach methods of horse riding (and also horse care) to beginners and improve the intermediate and advanced rider's style and technique.
 A riding instructor may also serve as a coach for a rider in competition.
 Some instructors may work out of their own riding facility, others at a riding school or training center.
 With appropriate academic credentials, some may teach in a college or university equestrian studies program.
 Yet others freelance and travel from stable to stable.
A riding school bus is a group of schoolchildren supervised by one or more adults, riding pedal cycles along a set route, picking kids up at "bus stops" along the way until they all arrive at school.
 Riding school buses are similar to walking bus programs.
 Like a traditional bus, riding school buses (also known as RSBs) have a fixed route with designated "bus stops" and "pick up times" in which they pick up children.
 Ideally the riding school bus will include at least 1 adult ‘driver’, who leads the group, and an adult ‘conductor' who supervises from the end of the group.
Max Ritter von Weyrother (1783–1833) was Chief Rider of the Spanish Riding School in Vienna from 1813, and Director from 1814 to 1833.
Gottlieb Polak (born January 13, 1883 in Kladruby nad Labem, died July 5, 1942 in Vienna) was Chief Rider and Riding Master of the Spanish Riding School in Vienna during the 1930s, serving until his death in 1942.

Question: Who was the chief rider at a traditional riding school for Lipizzan horses in the 1900s?
Answer: Ernst Lindenbauer