In 1915, Long established a private practice in Winnfield, through which he typically represented small plaintiffs, "the small man - the under-dog" according to Long.
These were usually workers' compensation cases.
He often said proudly that he never took a case against a poor man.
He was noted for successfully defending an impoverished widow against the Winnfield Bank.
Around this time, Long evaded fighting in World War I, claiming "I was not mad at anybody over there," and successfully defended a state senator from prosecution under the Espionage Act of 1917.
In 1918, Long invested $1,050 in an oil well that eventually struck oil.
But the well was unable to generate any income because the powerful Standard Oil Company refused to accept any of its oil in its pipelines, costing Long his investment.
This episode served as the catalyst for Long's lifelong hatred of Standard Oil, which he later denounced as an "invisible empire" run by "petroleumites."

That same year, Long entered into the race to serve on the three-seat Louisiana Railroad Commission.
According to historian William Ivy Hair, Long's political message:
... would be repeated until the end of his days: he was a young warrior of and for the plain people, battling the evil giants of Wall Street and their corporations; too much of America's wealth was concentrated in too few hands, and this unfairness was perpetuated by an educational system so stacked against the poor that (according to his statistics) only fourteen out of every thousand children obtained a college education.
The way to begin rectifying these wrongs was to turn out of office the corrupt local flunkies of big business ... and elect instead true men of the people, such as [himself].

In the Democratic primary, Long came in second behind incumbent Burk Bridges.
Since no candidate garnered a majority of the votes, a run-off election was held, for which Long campaigned tirelessly across the whole north of the state.
The race was incredibly close: Long managed to defeat Burk by just 636 votes.
Although the returns revealed wide support for Long in rural areas, Long performed poorly in the urban areas of Alexandria, Shreveport, and Monroe.
The Louisiana Railroad Commission and its members were known for largely having yielded to businesses and their owners.
However, once sworn in to office, Long refused to conform to their norms.
He forced utilities to lower rates, ordered railroads to extend service to small towns, and demanded that Standard Oil cease the importation of Mexican crude oil and use more oil from Louisianian wells.

In the gubernatorial election of 1920, Long campaigned heavily for John M. Parker; today Long is often credited with helping Parker to win in the northern Louisiana parishes.
But after Parker was elected, the two became bitter rivals.
This break was largely the result of Long demanding that Parker declare the state's oil pipelines to be public utilities, and Parker refusing to do so.
In particular, Long was infuriated when Parker allowed the oil companies, led by the legal team of Standard Oil, to assist in writing the state's severance tax laws, which decreed the amount corporations such as Standard Oil had to pay the state for the extraction of natural resources.
Long denounced Parker as corporate "chattel".
The feud climaxed in 1921, when Parker tried, unsuccessfully, to have Long ousted from his position on the commission.

By 1922, the Railroad Commission had been renamed the "Public Service Commission" and Long had gained the more powerful position of chairman.
That year, Long prosecuted the Cumberland Telephone & Telegraph Company for unfair rate increases; he successfully argued the case on appeal before the United States Supreme Court, resulting in cash refunds totaling $440,000 being sent to 80,000 overcharged customers.
After the decision, Chief Justice William Howard Taft praised Long as "the most brilliant lawyer who ever practiced before the United States Supreme Court."
In 1915, Long established a private practice in Winnfield, through which he typically represented small plaintiffs, "the small man - the under-dog" according to Long. These were usually workers' compensation cases. He often said proudly that he never took a case against a poor man. He was noted for successfully defending an impoverished widow against the Winnfield Bank. Around this time, Long evaded fighting in World War I, claiming "I was not mad at anybody over there," and successfully defended a state senator from prosecution under the Espionage Act of 1917. In 1918, Long invested $1,050 in an oil well that eventually struck oil. But the well was unable to generate any income because the powerful Standard Oil Company refused to accept any of its oil in its pipelines, costing Long his investment. This episode served as the catalyst for Long's lifelong hatred of Standard Oil, which he later denounced as an "invisible empire" run by "petroleumites." 
That same year, Long entered into the race to serve on the three-seat Louisiana Railroad Commission. According to historian William Ivy Hair, Long's political message:
... would be repeated until the end of his days: he was a young warrior of and for the plain people, battling the evil giants of Wall Street and their corporations; too much of America's wealth was concentrated in too few hands, and this unfairness was perpetuated by an educational system so stacked against the poor that (according to his statistics) only fourteen out of every thousand children obtained a college education. The way to begin rectifying these wrongs was to turn out of office the corrupt local flunkies of big business ... and elect instead true men of the people, such as [himself].
In the Democratic primary, Long came in second behind incumbent Burk Bridges. Since no candidate garnered a majority of the votes, a run-off election was held, for which Long campaigned tirelessly across the whole north of the state. The race was incredibly close: Long managed to defeat Burk by just 636 votes. Although the returns revealed wide support for Long in rural areas, Long performed poorly in the urban areas of Alexandria, Shreveport, and Monroe. The Louisiana Railroad Commission and its members were known for largely having yielded to businesses and their owners. However, once sworn in to office, Long refused to conform to their norms. He forced utilities to lower rates, ordered railroads to extend service to small towns, and demanded that Standard Oil cease the importation of Mexican crude oil and use more oil from Louisianian wells.
In the gubernatorial election of 1920, Long campaigned heavily for John M. Parker; today Long is often credited with helping Parker to win in the northern Louisiana parishes. But after Parker was elected, the two became bitter rivals. This break was largely the result of Long demanding that Parker declare the state's oil pipelines to be public utilities, and Parker refusing to do so. In particular, Long was infuriated when Parker allowed the oil companies, led by the legal team of Standard Oil, to assist in writing the state's severance tax laws, which decreed the amount corporations such as Standard Oil had to pay the state for the extraction of natural resources. Long denounced Parker as corporate "chattel". The feud climaxed in 1921, when Parker tried, unsuccessfully, to have Long ousted from his position on the commission.
By 1922, the Railroad Commission had been renamed the "Public Service Commission" and Long had gained the more powerful position of chairman. That year, Long prosecuted the Cumberland Telephone & Telegraph Company for unfair rate increases; he successfully argued the case on appeal before the United States Supreme Court, resulting in cash refunds totaling $440,000 being sent to 80,000 overcharged customers. After the decision, Chief Justice William Howard Taft praised Long as "the most brilliant lawyer who ever practiced before the United States Supreme Court."
Huey Long